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  • Statistical Physics  (2,408)
  • Animals  (1,602)
  • Cell & Developmental Biology
  • 42.75
  • AERODYNAMICS
  • 2015-2019  (4,052)
  • 1925-1929  (173)
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  • 1
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    In:  Nederlandse Faunistische Mededelingen (0169-2453) vol.46 (2016) p.115
    Publication Date: 2018-12-13
    Description: Oligochaete wormen komen vooral in zoet water voor. Maar in brak water en zelfs in de volle zee komen enkele soorten voor. Bij onderzoek naar marien benthos werden deze dieren traditioneel niet tot op soort gedetermineerd, omdat ze klein en lastig te determineren zijn. Ze zijn echter niet veel lastiger dan de nauw verwante Polychaeta, die ook hele kleine vertegenwoordigers kennen. In dit artikel wordt een overzicht gegeven van de 32 soorten die nu uit het zoute water in ons land bekend zijn, waarvan er hier zes als nieuw voor de Nederlandse fauna gepresenteerd worden. De vondst van Heterodrilus subtilis in de Noordzee is zeer bijzonder, omdat deze soort verder alleen bekend is van het typemateriaal, dat ongeveer honderd jaar geleden in de Golf van Napels werd verzameld.
    Keywords: Oligochaeta ; Nederland ; verspreiding ; herkenning ; biologie ; 42.75
    Repository Name: National Museum of Natural History, Netherlands
    Type: Article / Letter to the editor
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  • 2
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    In:  Nederlandse Faunistische Mededelingen (0169-2453) vol.46 (2016) p.87
    Publication Date: 2018-12-13
    Description: Het laatste overzicht van de wantsen van de Nederlandse waddeneilanden dateert van 2012. Een opsomming wordt gegeven van 43 nieuwe eilandrecords, waaronder vijf soorten die voor het eerst op de waddeneilanden zijn waargenomen. In totaal zijn er nu 380 soorten wantsen van de Nederlandse waddeneilanden bekend.
    Keywords: Heteroptera ; Nederland ; Waddeneilanden ; verspreiding ; 42.75
    Repository Name: National Museum of Natural History, Netherlands
    Type: Article / Letter to the editor
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  • 3
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    In:  Nederlandse Faunistische Mededelingen (0169-2453) vol.46 (2016) p.57
    Publication Date: 2018-12-13
    Description: Een overzicht wordt gegeven van waarnemingen van 33 soorten nieuwe of anderszins interessante soorten wantsen. Psallus aethiops (Miridae), Empicoris rubromaculatus (Reduviidae), Arocatus melanocephalus, Lygaeus simulans, Eremocoris fenestratus (Lygaeidae) en Nezara viridula (Pentatomidae) zijn nieuw voor de Nederlandse lijst, die daarmee nu 640 soorten telt. Naast nieuwe waarnemingen van zeldzame soorten wordt de recente uitbreiding van Cymatia rogenhoferi (Corixidae), Cardiastethus fasciiventris (Anthocoridae), Arocatus longiceps en Rhyparochromus vulgaris (Lygaeidae), Leptoglossus occidentalis (Coreidae), en Peribalus strictus en Rhaphigaster nebulosa (Pentatomidae) in kaart gebracht.
    Keywords: Heteroptera ; Nederland ; verspreiding ; 42.75
    Repository Name: National Museum of Natural History, Netherlands
    Type: Article / Letter to the editor
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  • 4
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    In:  Nederlandse Faunistische Mededelingen (0169-2453) vol.46 (2016) p.101
    Publication Date: 2018-12-13
    Description: In Nederland komen tien soorten ruighaarkevers (genera Dryops en Pomatinus) voor. Ze leven langs oevers van stilstaande en stromende wateren. Het was een verrassing toen in 2014 een vrouwtje van de zeer zeldzame Dryops striatellus gevonden werd bij Bakkeveen (provincie Friesland). De soort was sinds 1960 niet meer in Nederland gevonden. In 2016 werd D. striatellus op een tweede locatie nabij Bakkeveen gevonden. In dit artikel geven wij informatie over de soort en presenteren bijzonderheden over de Friese populatie en haar habitat.
    Keywords: Coleoptera ; Dryopidae ; Dryops striatellus ; Nederland ; verspreiding ; herkenning ; biologie ; 42.75
    Repository Name: National Museum of Natural History, Netherlands
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  • 5
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    In:  Nederlandse Faunistische Mededelingen (0169-2453) vol.46 (2016) p.11
    Publication Date: 2018-12-13
    Description: Op 14 oktober 2015 werd een halmvlieg met fraaie zwarte vlekken op de vleugels gefotografeerd in Hoogerheide (Noord-Brabant). Na vergelijking van foto’s werd geconcludeerd dat het moest gaan om Gampsocera numerata, welke determinatie later werd bevestigd. Reeds in 2009 bleek in België een mannetje van de soort gefotografeerd te zijn in een tuin in Evere. Ook in 2010 en 2015 is de soort in België gevonden. Dit zijn de eerste meldingen van G. numerata voor Nederland en België.
    Keywords: Diptera ; Chloropidae ; Gampsocera numerata ; Nederland ; België ; verspreiding ; herkenning ; biologie ; 42.75
    Repository Name: National Museum of Natural History, Netherlands
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  • 6
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    In:  Nederlandse Faunistische Mededelingen (0169-2453) vol.46 (2016) p.49
    Publication Date: 2018-12-13
    Description: Recently two exotic tubeworms new to the fauna of the Netherlands have been recorded in inshore waters in the delta area: Desdemona ornata and Pseudopolydora paucibranchiata. Within the Polychaeta these worms belong to the group of the Sedentaria. These construct a tube, in which the body of the worm is hidden. The head and feeding appendages protrude from the opening. Most probably these tubes are a major factor in the transport of these animals around the world, as they provide excellent shelters when they are attached to the hull of a ship or commercially traded shellfish.
    Keywords: Polychaeta ; Pseudopolydora paucibranchiata ; Desdemona ornata ; Nederland ; verspreiding ; exoot ; 42.75
    Repository Name: National Museum of Natural History, Netherlands
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  • 7
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    In:  Nederlandse Faunistische Mededelingen (0169-2453) vol.47 (2016) p.31
    Publication Date: 2018-12-13
    Description: De boszandbij Andrena coitana leek verdwenen uit Nederland. Veertig jaar na de laatste waarneming in 1975 is weer een populatie van deze soort gevonden, bij Epe in Gelderland. De boszandbij is een kleine soort, die mogelijk nog op sommige plaatsen over het hoofd gezien is. In dit artikel wordt de kennis over deze bijzondere bij samengevat en gespeculeerd over de oorzaken van de achteruitgang in Nederland.
    Keywords: Hymenoptera ; Apidae ; Andrena coitana ; Nederland ; verspreiding ; herkenning ; biologie ; 42.75
    Repository Name: National Museum of Natural History, Netherlands
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  • 8
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    In:  Nederlandse Faunistische Mededelingen (0169-2453) vol.46 (2016) p.1
    Publication Date: 2018-12-13
    Description: In 2015 werd Kelisia monoceros voor het eerst in ons land verzameld bij Kamperland in Zeeland. Deze spoorcicade leeft op de algemeen voorkomende valse voszegge. De vondst wijst op een recente areaaluitbreiding. Een andere spoorcicade, Ditropsis flavipes, werd al eerder uit ons land gemeld, maar verspreidingsgegevens worden nu voor de eerste maal gepubliceerd. Ditropsis flavipes leeft monofaag op bergdravik, een in Nederland zeldzaam gras.
    Keywords: Homoptera ; Delphacidae ; Nederland ; verspreiding ; biologie ; Kelisia monoceros ; Ditropsis flavipes ; herkenning ; 42.75
    Repository Name: National Museum of Natural History, Netherlands
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  • 9
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    In:  Nederlandse Faunistische Mededelingen (0169-2453) vol.47 (2016) p.17
    Publication Date: 2018-12-13
    Description: Alle spinnen hebben gif in hun kaken om hun prooien te doden. Verreweg de meeste soorten kunnen de menselijke huid niet doorboren met hun kaken en zijn dus volkomen ongevaarlijk. Kogelspinnen uit het genus Latrodectus, oftewel weduwen, vormen een uitzondering. Deze exotische spinnen worden af en toe geïmporteerd in Nederland. In 2013 is het aantal vondsten van geïmporteerde Latrodectus-spinnen op een rij gezet in een risicobeoordeling, met als resultaat een lijst van tien records met bewijsmateriaal. Hier kunnen nu vier records aan toegevoegd worden. Hieronder bevindt zich een vondst van de bruine weduwe L. geometricus, die recent voor het eerst in ons land werd vastgesteld, en een eerste geval van uitgekomen eitjes van een Latrodectus in ons land, van de roodrugspin L. hasselti.
    Keywords: Araneae ; Theridiidae ; Latrodectus ; Nederland ; exoot ; verspreiding ; 42.75
    Repository Name: National Museum of Natural History, Netherlands
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  • 10
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    In:  Nederlandse Faunistische Mededelingen (0169-2453) vol.47 (2016) p.27
    Publication Date: 2018-12-13
    Description: In 2015 werd tijdens een monitoringsproject van mariene bodemfauna op het Friese front de vulkaanworm Maxmuelleria lankesteri aangetroffen. Dit is de eerste vondst in Nederlandse wateren. De vulkaanworm dankt zijn naam aan de vorm van de opening van zijn leefgang, een vulkaanachtige slibheuvel. Het is opmerkelijk dat deze grote, opvallende worm (12-18 cm lang) niet eerder is aangetroffen. Mogelijk ligt dit aan de ongebruikelijke bemonsteringsmethode. Anderzijds kan de vulkaanworm daadwerkelijk zeldzaam zijn.
    Keywords: Echiura ; Maxmuelleria lankesteri ; Nederland ; verspreiding ; herkenning ; 42.75
    Repository Name: National Museum of Natural History, Netherlands
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  • 11
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    In:  Nederlandse Faunistische Mededelingen (0169-2453) vol.46 (2016) p.95
    Publication Date: 2018-12-13
    Description: De kleine bleekvlekwespbij Nomada baccata behoort tot een complex van taxa rond de bleekvlekwespbij Nomada alboguttata. De kleine bleekvlekwespbij is vroeger verspreid over het land aangetroffen, maar de laatste waarneming dateerde alweer van 1992. In de afgelopen jaren werd de soort op twee plekken in ons land teruggevonden, in de Schoorlse duinen in Noord-Holland in 2012 en op de Tongerense hei bij Epe in Gelderland in 2015.
    Keywords: Hymenoptera ; Apidae ; Nomada baccata ; taxonomie ; verspreiding ; herkenning ; biologie ; 42.75
    Repository Name: National Museum of Natural History, Netherlands
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  • 12
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    In:  Nederlandse Faunistische Mededelingen (0169-2453) vol.46 (2016) p.37
    Publication Date: 2018-12-13
    Description: De familie der sluipvliegen is één van de soortenrijkste vliegenfamilies in ons land. De larven ontwikkelen zich inwendig in ongewervelden, veelal vlinderrupsen. De groep is in ons land relatief goed bestudeerd en de afgelopen jaren zijn diverse aanvullingen op de checklist uit 2002 gepubliceerd. In dit artikel worden wederom twee soorten voor het eerst uit ons land vermeld. Hiermee komt het totaal aantal soorten dat in Nederland is vastgesteld op 336. Daarnaast wordt de herontdekking van een soort beschreven die al meer dan een eeuw niet meer waargenomen was.
    Keywords: Diptera ; Tachinidae ; Nederland ; verspreiding ; herkenning ; biologie ; 42.75
    Repository Name: National Museum of Natural History, Netherlands
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  • 13
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    In:  Nederlandse Faunistische Mededelingen (0169-2453) vol.46 (2016) p.15
    Publication Date: 2018-12-13
    Description: Canacidae zijn gebonden aan de kust en zou je daarmee typisch Nederlandse vliegjes kunnen noemen. In dit artikel melden wij een nieuwe soort van deze familie: Canace nasica en presenteren we een nieuwe Nederlandse checklist voor de familie. Naar de nieuwste taxonomische inzichten wordt daarbij de familie Tethinidae als subfamilie onder de Canacidae toegevoegd. Hiermee is de Nederlandse fauna een vliegenfamilie armer.
    Keywords: Diptera ; Canacidae ; Canace nasica ; Nederland ; herkenning ; verspreiding ; biologie ; 42.75
    Repository Name: National Museum of Natural History, Netherlands
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  • 14
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    In:  Nederlandse Faunistische Mededelingen (0169-2453) vol.47 (2016) p.11
    Publication Date: 2018-12-13
    Description: De kassprinkhaan is een buitenbeentje onder de Nederlandse sprinkhanen en krekels. Ze komt van oorsprong waarschijnlijk voor in grotten in Oost-Azië en is door transport van eieren met plantenmateriaal over de hele wereld verspreid geraakt. Ze kan tijdelijk overleven in het kunstmatig grotmilieu van bijvoorbeeld kruipruimtes van woonhuizen, in kassen en tuincentra. Recentelijk werd een opmerkelijk grote populatie van de kassprinkhaan gevonden in het uitgebreide stelsel aan kruipruimtes onder een verpleeghuis in Friesland. De kassprinkhaan blijkt hier al ruim 40 jaar voor te komen. Het is waarschijnlijk de grootste Europese populatie van deze soort.
    Keywords: Orthoptera ; Diestrammena asynamora ; verspreiding ; exoot ; 42.75
    Repository Name: National Museum of Natural History, Netherlands
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  • 15
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    In:  Nederlandse Faunistische Mededelingen (0196-2453) vol.46 (2016) p.43
    Publication Date: 2018-12-13
    Description: In het kader van het project ‘Duik de Noordzee Schoon’ worden scheepswrakken onderzocht, beschreven en van afval ontdaan. Scheepswrakken vormen een bijzonder leefgebied in het mariene milieu, met een hoge biodiversiteit. Dit bleek weer tijdens onderzoek van visnetten die van ver weg gelegen wrakken waren verwijderd. Hierbij werden maar liefst vier nieuwe mosdiertjes voor de Nederlandse fauna aangetroffen.
    Keywords: Bryozoa ; Nederland ; verspreiding ; 42.75
    Repository Name: National Museum of Natural History, Netherlands
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  • 16
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    In:  Nederlandse Faunistische Mededelingen (0169-2453) vol.47 (2016) p.43
    Publication Date: 2018-12-13
    Description: Pauropoda of weinigpoten zijn nauw verwant aan de miljoenpoten en duizendpoten. Het is een weinig bestudeerde diergroep, die bestaat uit kleine, witte en blinde bodemdieren die nauwelijks opvallen. Het meest kenmerkende zijn de gevorkte antennen, die wat bouw betreft uniek zijn ten opzichte van andere ongewervelden. Er zijn slechts acht soorten gemeld uit Nederland, alle behorend tot het genus Allopauropus. Recentelijk is een nieuwe soort, uit het genus Pauropus, in het westen van het land aangetroffen. Het betreft dus ook een nieuw genus voor de Nederlandse fauna. In dit artikel wordt de nieuwe soort voorgesteld, beschrijven we de habitat en geven we informatie over de verspreiding.
    Keywords: Myriapoda ; Pauropoda ; Pauropus lanceolatus ; Nederland ; verspreiding ; herkenning ; biologie ; 42.75
    Repository Name: National Museum of Natural History, Netherlands
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  • 17
    Publication Date: 2017-12-07
    Description: In Nederland zijn natuurlijke en semi-natuurlijke graslanden relatief slecht onderzocht op de aanwezigheid van springstaarten. In de ons omringende landen zijn deze biotopen vaak rijk aan specifieke soorten die alleen daar voorkomen. Naar verwachting kunnen in dit milieu veel nieuwe soorten voor onze fauna gevonden worden, vooral op nutriëntarme, zandige en droge ondergrond. Recentelijk zijn twee soorten uit het genus Folsomides in graslanden in het zuiden van ons land aangetroffen. Het betreft hier een nieuw genus voor de Nederlandse fauna. In dit artikel worden het genus en de twee soorten voorgesteld, beschrijven we de habitat en geven we informatie over de verspreiding en begeleidende soorten van deze springstaarten.
    Keywords: Collembola ; Isotomidae ; Folsomides ; verspreiding ; Nederland ; herkenning ; 42.75
    Repository Name: National Museum of Natural History, Netherlands
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  • 18
    Publication Date: 2017-12-07
    Description: Psilota is een genus van kleine, zwarte zweefvliegen, waarvan de larven leven achter boomschors. In 1988 werd Psilota anthracina voor het eerst in Nederland waargenomen en lange tijd is het een zeldzame soort geweest. De laatste jaren wordt ze steeds algemener, vermoedelijk door een veranderd bosbeheer. Gaandeweg is gebleken dat er een tweede soort onder schuilging; P. atra. Toen in België een derde soort opdook was het wachten tot deze ook in Nederland aangetroffen zou worden. In 2012 was het zover. Als Nederlandse naam stellen we voor spichtige spitsbek.
    Keywords: Diptera ; Syrphidae ; Psilota ; verspreiding ; Nederland ; herkenning ; 42.75
    Repository Name: National Museum of Natural History, Netherlands
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  • 19
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    In:  Nederlandse Faunistische Mededelingen (0169-2453) vol.45 (2015) p.51
    Publication Date: 2017-12-07
    Description: Het voorkomen van Badonnelia titei in ons land wordt in enkele publicaties genoemd. Deze exoot blijkt niet zeldzaam in archiefdepots overal in Nederland. In deze publicaties werd echter geen aandacht besteed aan het feit dat de soort nog niet als nieuw voor Nederland was gemeld, waar bewijsexemplaren zijn ondergebracht en hoe B. titei te herkennen is. De soort is daarom dan ook nooit doorgedrongen tot de diverse faunaoverzichten van Nederlandse stofluizen. Reden genoeg om deze zaken te behandelen in dit artikel, waarbij tevens een vindplaatsenkaartje wordt gegeven en de eerste vondsten uit woonhuizen worden gemeld.
    Keywords: Psocodea ; Sphaeropsocidae ; Badonnelia titei ; verspreiding ; Nederland ; exoot ; 42.75
    Repository Name: National Museum of Natural History, Netherlands
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  • 20
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    In:  Nederlandse Faunistische Mededelingen (0169-2453) vol.44 (2015) p.1
    Publication Date: 2017-12-07
    Description: De omgeving van Ommen en Hardenberg is het enige gebied in Nederland waar alle vier de soorten rode bosmieren voorkomen, waaronder de in Noordwest-Europa zeer zeldzame stronkmier. Recent is aan de alarmbel getrokken omdat het niet goed gaat met deze soort. Aanleiding voor een nieuw onderzoek bij Ommen, waarbij alle bosmieren onder de loep zijn genomen.
    Keywords: Hymenoptera ; Formicidae ; Formica ; verspreiding ; Nederland ; 42.75
    Repository Name: National Museum of Natural History, Netherlands
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  • 21
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    In:  Contributions to Zoology (1875-9866) vol.84 (2015) nr.4 p.305
    Publication Date: 2015-12-07
    Description: Firm coupling of genitalia is critical for copulation in most groups of insects. To counter female resistance that usually breaks off genital connection, male scorpionflies (Mecoptera: Panorpidae) usually provide nuptial gifts for the female and seize their mates with grasping devices. The notal organ, a modified clamp on tergum III of male scorpionflies, plays a significant role in seizing the female wings and helping maintain mating position during copulation. The mating behaviour remains unknown for the scorpionfly Furcatopanorpa longihypovalva (Hua and Cai, 2009) whose male lacks a notal organ. In this paper, we first attempt to study the mating behaviour of F. longihypovalva. The results show that the male provides liquid salivary secretion through a mouth-to-mouth mode for the female, and maintains copulation mainly by continuous provision of salivary secretion rather than by seizing the female with grasping devices. Thus the male copulates with the female in an atypical O-shaped position, with only their mouthparts and genitalia connected to each other. The salivary glands exhibit remarkable sexual dimorphism: short and bifurcated in the female, but well-developed and multi-furcated in the male. The extremely developed salivary glands of the male lay a structural foundation for the male to continuously provide liquid salivary secretion, and to help the male to mediate female resistance, being likely to serve as a compensation to his absence of the notal organ. We also investigated the functional morphology and copulatory mechanism of the male and female genitalia. The evolution of the atypical mating pattern of F. longihypovalva is putatively discussed as an adaptation in the context of sexual conflict.
    Keywords: Mecoptera ; Panorpidae ; Furcatopanorpa longihypovalva ; mating behaviour ; nuptial feeding, ; salivary glands ; genitalia ; functional morphology ; copulation ; 42.75 ; 42.62
    Repository Name: National Museum of Natural History, Netherlands
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  • 22
    Publication Date: 2015-11-10
    Description: Female genitalia are widely underrepresented in taxonomic studies. Here we investigate the morphological variation among female copulation organs for a group of scarab beetles (Sericini) with similar ecology, external morphology and copulation mechanics. We examined traits qualitatively and quantitatively based on 80 and 18 species (genus Pleophylla), respectively. Additionally we explored whether female genitalia are affected by asymmetry. The vast diversity of slerotised structures including their shapes illustrated the high taxonomic and phylogenetic utility of female genitalia in this group. The morphometric analysis of Pleophylla, confirmed that sclerotisations in the ductus bursae are very suitable for species-level taxonomic purposes. Stable interspecific variation is more hardly discernable in other parts such as the vaginal palps (shape and size) or the other membranous structures such as the shape of the bursa copulatrix. Asymmetric genitalia that arose multiple times independently among insects are found in most of the examined Sericini species. Asymmetries regarded either the bursa copulatrix, or both the bursa copulatrix and ductus bursae and comprised sclerotised and non-sclerotised structures being most common in modern Sericini. Here, highly asymmetric sclerotised structures are linked with strong asymmetry of the male copulation organs. Widespread asymmetry among megadiverse Sericini with a complex male-female genital asymmetry suggests that the shift to asymmetry is phylogenetically rather conserved. From the range of hypotheses, sexual selection seems to be the most reasonable to explain the evolution and stability of asymmetry in chafer genitalia.
    Keywords: beetles ; female genitalia ; integrative taxonomy ; Melolonthinae ; morphology ; 42.75 ; 42.64 ; 42.62
    Repository Name: National Museum of Natural History, Netherlands
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  • 23
    Publication Date: 2021-04-25
    Description: Niphargus is a speciose amphipod genus found in groundwater habitats across Europe. Three Niphargus species living in the sulphidic Frasassi caves in Italy harbour sulphur-oxidizing Thiothrix bacterial ectosymbionts. These three species are distantly related, implying that the ability to form ectosymbioses with Thiothrix may be common among Niphargus. Therefore, Niphargus-Thiothrix associations may also be found in sulphidic aquifers other than Frasassi. In this study, we examined this possibility by analysing niphargids of the genera Niphargus and Pontoniphargus collected from the partly sulphidic aquifers of the Southern Dobrogea region of Romania, which are accessible through springs, wells and Movile Cave. Molecular and morphological analyses revealed seven niphargid species in this region. Five of these species occurred occasionally or exclusively in sulphidic locations, whereas the remaining two were restricted to nonsulphidic areas. Thiothrix were detected by PCR on all seven Dobrogean niphargid species and observed using microscopy to be predominantly attached to their hosts' appendages. 16S rRNA gene sequences of the Thiothrix epibionts fell into two main clades, one of which (herein named T4) occurred solely on niphargids collected in sulphidic locations. The other Thiothrix clade was present on niphargids from both sulphidic and nonsulphidic areas and indistinguishable from the T3 ectosymbiont clade previously identified on Frasassi-dwelling Niphargus. Although niphargids from Frasassi and Southern Dobrogea are not closely related, the patterns of their association with Thiothrix are remarkably alike. The finding of similar Niphargus-Thiothrix associations in aquifers located 1200 km apart suggests that they may be widespread in European groundwater ecosystems.
    Keywords: amphipods; ecology; sulphide; symbiosis; systematics; taxonomy ; 551 ; Amphipoda ; Animals ; DNA, Bacterial ; Ecosystem ; Groundwater ; Molecular Sequence Data ; Phylogeny ; RNA, Ribosomal, 16S ; Romania ; Sequence Analysis, DNA ; Sulfur ; Symbiosis ; Thiothrix
    Language: English , English
    Type: article , publishedVersion
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  • 24
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    In:  Nederlandse Faunistische Mededelingen (0169-2453) vol.46 (2016) p.19
    Publication Date: 2018-12-13
    Description: Slakkendodende vliegen (familie Sciomyzidae) zijn al niet zo opvallend in het veld, maar de soorten uit de genera Pherbellia en Ditaeniella worden nog minder gevonden, mede doordat ze vrij klein zijn. De 14 Nederlandse soorten lijken sterk op elkaar. Dit artikel biedt een tabel om ze te kunnen herkennen en geeft informatie over ecologie en verspreiding.
    Keywords: Diptera ; Sciomyzidae ; Pherbellia ; Ditaeniella ; Nederland ; verspreiding ; herkenning ; biologie ; 42.75
    Repository Name: National Museum of Natural History, Netherlands
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  • 25
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    In:  Nederlandse Faunistische Mededelingen (0169-2453) vol.47 (2016) p.1
    Publication Date: 2018-12-13
    Description: Platwormen komen in Nederland vooral voor in zoet water, maar er zijn twee soorten van landbiotoop bekend. De laatste jaren duiken steeds vaker exotische landplatwormen op in Europa, vooral in kassen en tuincentra, maar sommige kunnen ook buitenshuis overleven. Uit Nederland zijn Bipalium kewense, Caenoplana bicolor en Marionfyfea adventor gemeld. Omdat ze regenwormen en slakken eten, kunnen ze een grote invloed hebben op het bodemleven, met gevolgen voor natuurlijke ecosystemen en landbouwgebieden. In het buitenland is de aandacht voor exotische landplatwormen al groeiende. Zo wordt de Nieuw-Guineese landplatworm Platydemus manokwari door de IUCN tot de 100 ergste invasieve soorten aangemerkt. In Nederland is er nog nauwelijks aandacht voor landplatwormen. Daarom wordt in dit artikel de kennis over deze groep samengevat.
    Keywords: Platyhelminthes ; Tricladida ; Nederland ; verspreiding ; biologie ; 42.75
    Repository Name: National Museum of Natural History, Netherlands
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  • 26
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    In:  Nederlandse Faunistische Mededelingen (0169-2453) vol.47 (2016) p.39
    Publication Date: 2018-12-13
    Description: Blaaskopvliegen zijn een van de groepen uit het atlasproject Leuke vliegen, dat in 2015 werd afgesloten. Het zijn over het algemeen opvallend gekleurde vliegen, die parasiteren bij bijen en wespen. In een overzichtsartikel uit 2014 werd de komst van Leopoldius calceatus al voorspeld en in 2015 werd soort inderdaad aangetroffen in Groeve Craubeek in de provincie Limburg en een jaar later op de Stratumse heide bij Eindhoven.
    Keywords: Diptera ; Conopidae ; Nederland ; Leopoldius calceatus ; verspreiding ; herkenning ; biologie ; 42.75
    Repository Name: National Museum of Natural History, Netherlands
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  • 27
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    In:  Nederlandse Faunistische Mededelingen (0169-2453) vol.47 (2016) p.49
    Publication Date: 2018-12-13
    Description: Astigmatic mites probably form the most diverse cohort of mites. At present the former order of Astigmatina is ranked within the suborder Oribatida or moss mites. However astigmatic mites occupy a much wider range of habitats than other oribatid mites: from marine coasts to stored food, plant bulbs and houses. The vast majority live as commensals or parasites on a variety of hosts, ranging from insects to birds and mammals, inhabiting the fur, feathers, skin and even lungs and stomach. This first checklist for the Netherlands contains 262 species, but many more are to be expected. Brief data on occurrence and nomenclature are provided for each species.
    Keywords: Acari ; Oribatida ; Astigmatina ; verspreiding ; taxonomie ; 42.75
    Repository Name: National Museum of Natural History, Netherlands
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  • 28
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    In:  Nederlandse Faunistische Mededelingen (0169-2453) vol.45 (2015) p.39
    Publication Date: 2017-12-07
    Keywords: Coleoptera ; Brentidae ; Exapion ulicis ; verspreiding ; Nederland ; herkenning ; biologie ; 42.75
    Repository Name: National Museum of Natural History, Netherlands
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  • 29
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    In:  Nederlandse Faunistische Mededelingen (0169-2453) vol.44 (2015) p.11
    Publication Date: 2017-12-07
    Description: Eikelwormen zijn mariene wormen die een eigen klasse vormen, de Enteropneusta. In Nederland zijn het ook de enige vertegenwoordigers van de kraagdragers (fylum Hemichordata). Het zijn bijzondere dieren, die nauwer verwant zijn aan stekelhuidigen en gewervelde dieren dan aan gelede wormen. Het lichaam is ongeleed, met een gesteelde slurf, met daarachter een kraag en een langwerpig lichaam met tientallen kieuwspleten. De wormen leven in een U-vormige buis in zachte bodems. In de loop van de tijd zijn wel eikelwormen langs de Nederlandse kust verzameld, maar deze zijn nooit op naam gebracht. In dit artikel wordt ingegaan op de eerste vondsten van eikelwormen in de Oosterschelde.
    Keywords: Enteropneusta ; Saccoglossus ; verspreiding ; Nederland ; 42.75
    Repository Name: National Museum of Natural History, Netherlands
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  • 30
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    In:  Nederlandse Faunistische Mededelingen (0169-2453) vol.44 (2015) p.47
    Publication Date: 2017-12-07
    Description: The gall midges are one of the most important groups of gall makers. Emerging larvae produce stimuli and the host plant responds by producing galls, fascinating structures which provide food and shelter for the developing larvae. Most gall inducing midges are host specific: they are only able to induce galls in a few, often related, plant species. A few species have different feeding modes: among them are saprophagous, fungivorous and predaceous species and some are used in biocontrol. We recorded 416 species in the whole area; 366 species are recorded from the Netherlands, 270 species from Belgium and 96 species from Luxembourg.
    Keywords: Diptera ; Cecidomyiidae ; Netherlands ; Belgium ; Luxembourg ; distribution ; biology ; 42.75
    Repository Name: National Museum of Natural History, Netherlands
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  • 31
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    In:  Nederlandse Faunistische Mededelingen (0169-2453) vol.45 (2015) p.19
    Publication Date: 2017-12-07
    Description: Het gebeurt met enige regelmaat dat er boorvliegen versleept worden met plantaardige producten. De meeste schadelijke soorten komen uit de tropen en kunnen zich niet handhaven in Nederland. Noord-Amerikaanse soorten van het genus Rhagoletis kunnen in het klimatologisch vergelijkbare Europa wel voet aan de grond krijgen. Eerder bleek dit al met de Oost-Amerikaanse kersenboorvlieg en nu staat hetzelfde te gebeuren met de walnootboorvlieg.
    Keywords: Diptera ; Tephritidae ; Rhagoletis completa ; verspreiding ; herkenning ; Nederland ; exoot ; 42.75
    Repository Name: National Museum of Natural History, Netherlands
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  • 32
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    In:  Nederlandse Faunistische Mededelingen (0169-2453) vol.45 (2015) p.13
    Publication Date: 2017-12-07
    Description: Door gebruik te maken van observatiekunstnestjes is het mogelijk om regelmatig een kijkje te nemen in de nesten van bijvoorbeeld graafwespen. Zij gebruiken de nesten om zich voort te planten. Zo kunnen we meer te weten komen over hun gedrag in het nest tijdens de voortplanting. In dit artikel worden de ervaringen met de graafwesp Psenulus fuscipennis beschreven. De verschillen in levenswijze met de kleine zeefwesp en bijenwolf worden toegelicht.
    Keywords: Hymenoptera ; Crabronidae ; Psenulus fuscipennis ; biologie ; 42.75
    Repository Name: National Museum of Natural History, Netherlands
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  • 33
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    In:  Nederlandse Faunistische Mededelingen (0169-2453) vol.45 (2015) p.7
    Publication Date: 2017-12-07
    Description: De gele tubebij Stelis signata was sinds 1977 niet meer in ons land aangetroffen. Men dacht daarom dat deze bij uit ons land verdwenen was. In 2013 werd de soort echter op Waarneming.nl gemeld van de Strabrechtse hei en in 2014 van Afferden. In 2015 werd een vrouwtje gevangen op de Sprengenberg op de Sallandse heuvelrug. In 2011 heeft Natuurmonumenten hier kleinschalige maatregelen uitgevoerd voor specifieke heidesoorten, waaronder de aanleg van een flink aantal steilranden. Het microreliëf dat daarbij ontstaat vormt een belangrijke nestelplaats voor bijen en wespen. De vondst van de zeldzame gele tubebij op een van deze steilranden vormt de kroon op het werk.
    Keywords: Hymenoptera ; Megachilidae ; Stelis signata ; verspreiding ; biologie ; Nederland ; 42.75
    Repository Name: National Museum of Natural History, Netherlands
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  • 34
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    In:  Nederlandse Faunistische Mededelingen (0169-2453) vol.44 (2015) p.37
    Publication Date: 2018-12-13
    Description: In 2007 werd Diplocoelus fagi bij Wageningen gevonden. De larven van deze kever leven in dood hout. Na de eerste vondst zijn diverse andere waarnemingen gedaan en D. fagi is nu bekend uit vier provincies. Omdat de soort in de omringende landen al lang bekend was, is deze late ontdekking opmerkelijk. Mogelijk hangt dit samen met het verbeterde bosbeheer, waarbij minder dood hout uit de bossen wordt verwijderd.
    Keywords: Coleoptera ; Biphyllidae ; Diplocoelus fagi ; verspreiding ; Nederland ; biologie ; herkenning ; 42.75
    Repository Name: National Museum of Natural History, Netherlands
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  • 35
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    In:  Nederlandse Faunistische Mededelingen (42.75) vol.44 (2015) p.29
    Publication Date: 2017-12-07
    Description: The snail-killing fly Salticella fasciata was discovered in Belgium in 2010. Since then, several new localities on the Belgian coast were discovered and in 2014, the first record for the Netherlands was found. This is the first representative of the genus and also of the subfamily Salticellinae in the Netherlands. In this paper, records from Belgium and the Netherlands are reviewed and information on biology and habitats is summarised.
    Keywords: Diptera ; Sciomyziidae ; Salticella fasciata ; Nederland ; België ; 42.75
    Repository Name: National Museum of Natural History, Netherlands
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  • 36
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    In:  Nederlandse Faunistische Mededelingen (0169-2453) vol.44 (2015) p.17
    Publication Date: 2017-12-07
    Description: Twaalf jaar geleden waren er nog geen Nelima-soorten bekend uit ons land. In 2004 en 2006 werden respectievelijk N. sempronii en N. doriae ontdekt. Beide soorten komen ten zuidoosten van ons land voor, en hebben naar alle waarschijnlijkheid Nederland recent bereikt. In 2012 werd op de Maasvlakte een derde vertegenwoordiger van dit genus gevonden: Nelima gothica. De vindplaats lijkt te wijzen op introductie door de mens. Gezien het voorkomen in de ons omringende landen is echter niet uit te sluiten dat hij van oudsher tot onze fauna behoort of recent op eigen kracht Nederland heeft bereikt. Hij zou op meer plaatsen langs de kust kunnen voorkomen. We presenteren de nieuwe soort en geven een overzicht van de vier Noordwest-Europese Nelima-soorten.
    Keywords: Opiliones ; Nelima ; verspreiding ; Nederland ; Europa ; 42.75
    Repository Name: National Museum of Natural History, Netherlands
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  • 37
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    In:  Nederlandse Faunistische Mededelingen (0169-2453) vol.45 (2015) p.1
    Publication Date: 2018-12-13
    Description: Goudwespen zijn fraaie insecten, met felle metaalkleuren in de tinten rood, groen en blauw. Ze parasiteren vaak bij bijen en angeldragende wespen. In dit artikel wordt de eerste vondst van Chrysis equestris voor Nederland beschreven, waarmee het aantal in Nederland gevonden soorten nu op 57 komt. Deze goudwesp parasiteert bij de plooivleugelwesp Discoelius zonalis. Ze wordt in haar hele areaal weinig gevangen.
    Keywords: Hymenoptera ; Chrysididae ; Chrysis equestris ; verspreiding ; biologie ; herkenning ; Nederland ; 42.75
    Repository Name: National Museum of Natural History, Netherlands
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  • 38
    Publication Date: 2016-02-09
    Description: Wing shape variation was investigated between the sexes and among four populations of the scorpionfly Dicerapanorpa magna (Chou, 1981) endemic to the Qin-Ba Mountains area, China through the landmark-based geometric morphometric approach. The results show that sexual dimorphism exists both in wing size and shape in D. magna. Significant differences exist in female wing size and shape among D. magna populations. The possible reasons of the wing variation are discussed based on the divergence time of D. magna in combination with the tectonic and climatic events in the Qin-Ba Mountains during the late Miocene-Pleistocene period. Whether reproductive isolation exists between different populations needs further research.
    Keywords: canonical variates analysis ; individual variation ; sexual dimorphism ; 42.75 ; 42.62
    Repository Name: National Museum of Natural History, Netherlands
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  • 39
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    In:  Nederlandse Faunistische Mededelingen (0169-2453) vol.45 (2015) p.91
    Publication Date: 2017-12-07
    Description: The Flevopark is one of the most special green areas of Amsterdam with a rich nature. Twelve oribatid mite species were collected here in 2014 from bark and mosses on trees. Liacarus acutus and Perlohmannia dissimilis are reported for the first time from the Netherlands. It is not clear if the newly recorded species have always been overlooked or are recent immigrants.
    Keywords: Acari ; Oribatida ; distribution ; Nederland ; 42.75
    Repository Name: National Museum of Natural History, Netherlands
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  • 40
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    In:  Nederlandse Faunistische Mededelingen (0169-2453) vol.45 (2015) p.77
    Publication Date: 2017-12-07
    Description: Watermijten zijn kleine spinachtige diertjes, die in zoet water leven. De aandacht voor deze diergroep is groot, omdat ze een rol spelen in de waterkwaliteitsbeoordeling. In de verspreidingsatlas uit 2000 worden 234 Nederlandse watermijten gemeld. Sinds die tijd worden regelmatig aanvullingen gerapporteerd. In dit artikel worden weer acht nieuwe soorten gemeld, wat het totaal nu op 266 brengt. Dit is een opmerkelijke toename van 13 % in 15 jaar.
    Keywords: Acari ; Hydrachnidia ; verspreiding ; Nederland ; 42.75
    Repository Name: National Museum of Natural History, Netherlands
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  • 41
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    In:  Nederlandse Faunistische Mededelingen (0169-2453) vol.45 (2015) p.67
    Publication Date: 2017-12-07
    Description: De publicatie van de naamlijst van de Nederlandse kieuwpootkreeften in 2002 was een grote stimulans voor nieuw onderzoek. Na de publicatie met aanvullingen in 2009 zijn er weer negen soorten bijgekomen, waarmee het totaal aantal soorten kieuwpootkreeften in Nederland nu op 124 komt. In dit artikel worden de nieuwe soorten besproken en wordt ingegaan op de redenen voor deze opmerkelijke uitbreiding.
    Keywords: Crustacea ; Branchiopoda ; Cladocera ; Nederland ; verspreiding ; 42.75
    Repository Name: National Museum of Natural History, Netherlands
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  • 42
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    In:  Nederlandse Faunistische Mededelingen (0169-2453) vol.45 (2015) p.33
    Publication Date: 2017-12-07
    Description: Prachtvliegen zijn vrij kleine vliegen die vaak een vleugeltekening hebben waardoor ze aan boorvliegen doen denken. De meeste soorten zijn weinig opvallend in het veld aanwezig en zitten vooral op hun waardplanten. Alleen de soorten waarvan de larven leven onder schors van boomstammen zijn opvallender aanwezig door hun balts of territoriaal gedrag. Ze proberen hun stukje boomstam te claimen door snel op en neer te lopen en tegelijkertijd driftig met hun vleugels te bewegen. Tot nog toe was de zeer fraaie Myennis octopunctata (Coquebert, 1798) de enige houtbewonende prachtvlieg in Nederland. In dit artikel wordt daar Homalocephala biumbrata aan toegevoegd.
    Keywords: Diptera ; Ulidiidae ; Homalocephala biumbrata ; verspreiding ; Nederland ; 42.75
    Repository Name: National Museum of Natural History, Netherlands
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  • 43
    Publication Date: 2015-11-07
    Description: Integrative taxonomy tests the validity of taxa using methods additional to traditional morphology. The existence of two different morphotypes in specimens identified as Chrysotoxum vernale Loew (Diptera: Syrphidae) prompted their taxonomic study using an integrative approach that included morphology, wing and male-surstylus geometric morphometrics, genetic and ecological analyses. As a result, a new species is recognised, Chrysotoxum montanum Nedeljković & Vujić sp. nov., and C. vernale is re-defined. A lectotype and paralectotypes are designated for C. vernale to stabilize this concept. An additional species, Chrysotoxum orthostylum Vujić sp. nov., with distinctive male genitalia is also described. The three species share an antenna with the basoflagellomere shorter than the scape plus pedicel and terga with yellow fasciae not reaching the lateral margins. This study confirms the value of integrative approach for resolving species boundaries.
    Keywords: Balkan Peninsula ; C. montanum sp. nov. ; C. orthostylum sp. nov. ; ecological niche ; geometric morphometry ; lectotype ; mtDNA COI sequences ; Syrphinae ; 42.75 ; 42.64 ; 42.62
    Repository Name: National Museum of Natural History, Netherlands
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  • 44
    Electronic Resource
    Electronic Resource
    New York, NY : Wiley-Blackwell
    Journal of Morphology 40 (1925) 
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Type of Medium: Electronic Resource
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  • 45
    Electronic Resource
    Electronic Resource
    New York, NY : Wiley-Blackwell
    Journal of Morphology 40 (1925), S. 517-557 
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: An early segregation of germ cells and migration through a germ track into the gonad does not occur in the albino rat. The germ cells are produced only from the peritoneum of the genital region and their earliest formation is coincident with the thickening of the coelomic epithelium to form the genital ridge. This takes place eleven days after insemination in embryos of approximately 18 somites. Germ cells continue to form from the peritoneum during the early development of the gonad. The peritoneum of this region also produces mesenchyme, smaller cells of the gonads, and the germinal epithelium.The argument for the specific character of the germ cells in vertebrates and their continuity from the egg is based largely upon assumption, and not upon substantial observations, and must be discarded. Germ-cell origin is a problem of cellular differentiatio, and not of early segregation.
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  • 46
    Electronic Resource
    Electronic Resource
    New York, NY : Wiley-Blackwell
    Journal of Morphology 41 (1925), S. ii 
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
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  • 47
    Electronic Resource
    Electronic Resource
    New York, NY : Wiley-Blackwell
    Journal of Morphology 41 (1925), S. 191-216 
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: Painted turtles, gopher tortoises, and terrapins were fed on various mixtures of sand, salts, dextrin, casein, cod-liver oil, wheat, eggs, lettuce, and meal worms. Each individual was weighted weekly for about a year and then killed for analysis, the water, ash, nitrogen, and fat being determined. Some individuals increased in weight as much as 75 per cent, others lost weight. Judged by growth and chemical analyses, the food requirements of chelonians, as representative poikilothermal vertebrates toward nutritive substances (including vitamines) are similar to those of homoiothermal animals.
    Additional Material: 13 Ill.
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  • 48
    Electronic Resource
    Electronic Resource
    New York, NY : Wiley-Blackwell
    Journal of Morphology 41 (1925), S. 267-281 
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: Of the eggs laid by Fasciolaria about 1 per cent develop into veligers, about 2 per cent more undergo a few cleavage divisions, and about 97 per cent do not divide at all. The 99 per cent that fail to develop normally are ‘swallowed’ by the veligers. This study concerns itself chiefly with the ova that do not divide. Notes on normal development and on the ova that undergo atypical cleavage are included.All of the ova are found to be typical when passed from the ovary. To each ovum one to several sperms become attached at the vegetal pole in the region of a mass of undifferentiated protoplasm - the ‘polar mass.’ A fertilization cone forms in each ovum and a fertilization membrane. In typical development a yolk lobe is formed, the sperm enters in the usual way, and fertilization is completed as in many other mollusks. In 97 per cent of the ova the yolk lobe is not formed and the sperm does not enter. In these cases the wall of the egg nucleus remains intact a long time. The nucleus itself and the ‘polar mass’ sink into the egg and meet at the center. Then the nuclear wall disappears and an atypical diaster is formed. However, cleavage is not begun and the chromosomes form vesicles that remain near the center of the ovum until it is ‘swallowed’ and digested by the veliger.
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  • 49
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: The blood of Perophora viridis is found to contain six types of cells: (1) Green cells, which have green-colored fatty bodies embedded in clear cytoplasm. (2) Orange cells, with orange-colored bodies of unknown composition in the cytoplasm. (3) Colorless berry-like cells, with fluid-filled vesicles in the cytoplasm. (4) Granular amoeboid cells. (5) Compartmental amoeboid cells, which have box-like vacuoles containing brownian granules of a fatty substance. (6) Vesicular, signet-ring type of cell having a single large vacuole. The cytological structure of these cells and their reaction to various dyes are described.An effort has been made to homologize the types of cells found in the blood of other ascidians with those found in Perophora.It is concluded that the variety of colors found in the cells of ascidian blood is due to the varying chemical states of the vanadium-containing chromogen present in the cells.
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  • 50
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    Journal of Morphology 42 (1926) 
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
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  • 51
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    Journal of Morphology 42 (1926), S. 111-141 
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    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: Disintegration in killing agents was studied throughout development. In the unfertilized egg and cleavage stages the death gradient runs from animal to vegetal pole. In the late blastula stage the future dorsal surface and future point of gastrulation show heightened susceptibility. The gastrula has a gradient from anterior to posterior end along its dorsal surface, with a slight reverse gradient around the blastopore; lateral and ventral regions are least susceptible.Before and after the appearance of the neural groove, the dorsal surface shows increased susceptibility with gradient in it from anterior to posterior end. The neural tube is highly susceptible, with a death gradient from anterior to posterior end and a slight reverse gradient at its posterior end.During late stages and in the larva the double gradient is present; death begins at the two ends and progresses backward from head, forward from anus; from the former most rapidly. The least susceptible place is near the posterior end. The posterior reverse gradient is less developed in the lamprey than in other vertebrate embryos, due, probably, to its lack of a tail bud.Assuming that death differences indicate differences in rate of activity, it appears that such differences in activity may be causes and not results of developmental processes, for the development of certain parts (dorsal surface, blastopore, central nervous system) is indicated by heightened activity before it is evident morphologically.
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  • 52
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    Journal of Morphology 42 (1926), S. 83-109 
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    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: The summary of this paper is as follows:1A critical review of the developmental evidence shows that the branchial pouches are formed in cephalocaudal sequence subsequently to the segmentation of the dorsal mesoderm.2The pouches interrupt a continuous sheet of mesoderm to form the branchial arches.3The arches when formed do not correspond topographically to the dorsal somites.4Branchiomerism does not therefore coincide with somitic metamerism.3The branchial structures do not support the theory of head segmentation.3The nervi trigeminus, facialis, glossopharyngeus, and vagus cannot be regarded as segmental nerves.3There is no evidence that branchial pouches or arches have been elided from the series.3The problem of meristic homology is briefly discussed.
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    Journal of Morphology 43 (1927), S. 521-546 
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    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: The literature on the general subject of freezing and survival both in plants and in animals is briefly reviewed and a bibliography given. Insects representing three ecological groups, (1) the oak borers - exposed to temperature extremes normally; (2) stored-products insects representing supposedly a tropical or subtropical group, and, (3) aquatic insects never exposed to temperatures lower than 0°C., were chosen for this study. Determinations of the freezing and undercooling points were made during the yearly cycle.Both the stored-products insects and the aquatic insects studied showed no periodicity in freezing or undercooling. The oak borers showed marked periodicity. The freezing-point varies directly with the moisture content. Cold-hardiness was produced experimentally by, (1) exposure of insects to low temperatures and, (2) by dehydration. Loss of cold-hardiness was produced experimentally by combinations of high temperature, food, and high relative humidity. The freezing-point ordinarily found corresponds with that of the blood. Repeated freezings of the same insect or tissue showed no hysteresis. There exists in certain insects a secondary freezing-point below that ordinarily found. Oak borers in summer condition die at the first freezing-point; in fully hardened condition they die at the secondary freezingpoint.
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    Journal of Morphology 44 (1927), S. 1-20 
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    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: The ant Formica exsectoides F. builds mounds with some reference to sunlight, and measurements of internal temperatures have shown them higher in upper parts of the mound, but different in different faces of the mound - all higher than the earth outside the mound.Inside temperatures are not constant; they are due to the sunshine. The mound is so fabricated that the internal temperatures are conserved during the night. The ants make use of the differential internal temperatures for rearing broods.Some mounds show bilateral symmetry dependent upon sun exposure.Measurements of rate of running of these ants show a falling off with lower temperatures, and possibly this is one factor in the smaller development of northerly aspects of these mounds.
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    Journal of Morphology 44 (1927), S. 117-125 
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    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
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    Notes: In the early cleavage stages of Ascaris the homologous chromosomes are of unequal length. Measurements show that these homologues fall into two sharply defined groups suggesting their biparental origin. The shorter are considered to have come from the male.As the age of the embryo increases, these differences between the chromosome mates tend to become less, and it is suggested that at some later period in the history of the animal this difference will entirely disappear in response to the effect of continued existence in a common environment. The length of the chromosomes is very slightly shortened during the early cleavage divisions, while the area of the equatorial cross-section of the cells becomes enormously reduced.
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    Journal of Morphology 44 (1927), S. 313-339 
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    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
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    Notes: The rates of oxygen consumption of single pupae of blowflies (Phormia terraenovae, Phormia regina, Lucilia sericata), of the flesh fly (Sarcophaga sarracenioides Aldrich), of the Mediterranean flour moth (Ephestia kuehniella), and of the bee moth (Galleria mellonella) during metamorphosis, until emergence, have been determined. The record for each pupa, with the exception of those of blowflies, is practically continuous day and night during the period of pupal development which lasted from 140 to 300 hours, according to the species, at the temperatures used. During pupal development there is first a period of decrease in rate, which is later followed by a steady increase until a short time before emergence, when a sudden decrease occurs.The ‘oxygen curves’ of the blowfly pupae (Diptera) are quite different from those of the flour-moth and bee-moth pupae (Lepidoptera), although all are of the same general U-shaped type. There are strong indications of a specific difference in the curves of the blow-fly pupae. The flour-moth pupae curves differ slightly from those of the bee-moth pupae. During the major part of development the rates of O2 consumption of pupae of both sexes of bee moth and flour moth are about the same, but near the end of metamorphosis the females have higher rates than the males. No such sex difference appears among the dipterous pupae used.
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    Journal of Morphology 44 (1927), S. 363-372 
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    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: The history of investigations on the contractile vacuole is reviewed briefly and brought up to date.The study of the contractile vacuole in Amoeba proteus is considered from standpoints of origin, structure, behavior, and function. The results are obtained from a prolonged study of normal organisms and from their reactions when introduced into conductivity water.The origin of vacuoles is studied by means of dark-field illumination which reveals the vacuole to be formed from a fusion and coalescence of extremely minute droplets.The retaining ‘wall’ of the contractile vacuole is not a permanent structure, but is in the nature of a condensation membrane, totally disappearing with each contraction.The loci of the contractile vacuoles are not permanent, but vacuoles are formed more or less at random. It is unlikely that they are supported in gelated areas, for amoebae with a dozen vacuoles are quite active and there is no interference with amoeboid movement.Conductivity water increases the size, number, and rate of contraction of contractile vacuoles, which suggests that they may function in maintaining an osmotic gradient as well as in the elimination of metabolic waste.
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    Journal of Morphology 44 (1927), S. 467-514 
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    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: The eggs of Corella develop in the atrial chamber of the parent at a pH below that of normal sea-water (pH 7.4 ±). When removed to normal sea-water in early stages and under certain other experimental conditions, larval development is more or less inhibited, the tail being most inhibited, the dorsal region somewhat less. The free larval stage may be eliminated and later development and metamorphosis may proceed normally to an advanced stage in the chorion and give rise to normal ascidians. The region most inhibited are, in general, those which possess the highest reducing power, as indicated by KMnO4. Experiments made in the attempt to control development all agree in indicating that the early stages are adjusted to a certain CO2 concentration approximately that of the atrial chamber and presumably near that of the body. Solutions of the same pH may or may not inhibit development according to their CO2 content.The tail, the region of highest reducing power in the embryo during its development, is most inhibited; the dorsal region, the next most rapidly reducing region, is next in degree of inhibition. All differences in reducing power disappear when, or soon after, the animals are killed by other agents before treatment with KMnO4.
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    Notes: The claspers of Centrina are adnate with the pelvic fin and bear a spine as in other Spinacidae. Mustelus canis resembles M. lunulatus rather than M. vulgaris. The claspers of Chiloscyllium end in a pointed spike. Pseudotriakis resembles the Carchariidae. The three North American Atlantic species of the genus Raia are considered, and R. laevis and R. erinacea are placed in the pseudogenus containing R. batis, and a new pseudogenus erected for R. ocellata. A gross and histological account is given of the Cowper's glands of Homo, and they are shown to be homoplastic with clasper glands, similar in structure, arrangement, development, and function.
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    Notes: In the golden-mantled ground-squirrel, Callospermophilus, a spatulate glandular area has been noted in the skin of the back. It has been found in the following species: C. l. lateralis, C. l. arizonensis, C. l. caryi, C. l. saturatus, C. l. tescorum, C. c. chrysodeirus, and C. bernardinus. Probably it is common to the genus.The individual glands making up this area are modified and enlarged sudoriparous glands. They are divided into a tightly coiled and branched fundus, a large sinus, and a duct which passes caudad and outward to its exit at the surface.The glands secrete a strongly smelling oil, which is probably left on vegetation and other objects in the animal's environment and serves as a source of information to other members of the species. The glands are more active in spring and summer than in winter. They are stimulated by excitement. While present in both sexes, both adult and juvenile, they are best developed in adult males.Callospermophilus has three anal glands. These have flat-topped, straight-sided nipples which are protruded from the anus if the animal is frightened. A milky substance with a very weak odor can be extruded.
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    Notes: The study is divided into three parts. Part I deals with the chromosome number and morphology in the amniotic cells of rabbit embryos. The number of chromosomes has been found essentially constant in amniotic cells of young, but more variable in older embryos. The somatic number is 44. Part II deals with the chromosomes of race crosses (Flemmish Giant X Polish) in which the homologous chromosomes were found to be alike. Part III deals with spermatogenesis. There are forty-four chromosomes in spermatogonia, and twenty-two in primary spermatocytes. The sex chromosomes are of the usual X-Y type.
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    Notes: 1Monovalent cation salts induce reversal in the direction of the stroke of the cilia; bivalent and trivalent cation salts with a few exceptions do not. Some acids induce reversal, others do not.2The duration of reversed action varies with the kind of salt and with the concentration. As the concentration increases, the duration of reversed action increases to a maximum and then decreases to zero.3Bivalent and trivalent cation salts neutralize the effect of monovalent cation salts. The relative amount required varies with the kind of salt used and with the concentration.4The amount of a given salt required to neutralize another salt is not proportional to the concentration of the salt neutralized. Weber's law does not hold.5The results seem to indicate that ciliary reversal is associated with differential adsorption and consequent changes in electric potential, but that there are also other factors involved.
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    Notes: A special type of cell, called ‘Lichtzellen’ by Hesse, was found in the photosensitive regions of the earthworm. Wherever the epidermis is most sensitive to light these cells are most abundant. They are found in the epidermis of all segments of the body and also in nerve enlargements of the prostomium and the caudal segment, but the intersegmental and ventral regions of the different segments, except the more distal ones, contain none of them. They are supplied by nerves and each contains a characteristic inner structure, the optic organelle, composed of a large central hyaline structure, the lens, which is surrounded by a dense network of nerve fibrillae, the retinella. In hanging drops the lens was found to focus light in the region of the retinella irrespective of the direction of the rays.These cells are similar in structure and function to the visual cells in leeches. Available data indicate that these cells function as photoreceptors and that the fibrillae of the retinella are the direct receptors of light stimuli.Pigment is not associated with the photoreceptors in a way that suggests direct functional relationship, but there is a subepidermal pigment layer through which pinhole windows admit light along the path of nerves to each of the nerve enlargements containing photoreceptor cells. These windows open in such directions as to determine the direction of withdrawal of the worm.
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    Notes: The effect of removal of the liver has been noted in fishes, frogs, and turtles. As in the higher vertebrates, removal of the liver produced a fall in blood sugar and a loss in muscular tone. The lower vertebrates failed to respond to intravenous injections of glucose, as do the birds and mammals. They also fail to respond to maltose or levulose. The liver maintained the blood-sugar level in the lower vertebrates, which is necessary for the maintenance of life.The mechanism of carbohydrate metabolism in the lower vertebrates may be different from that in the higher ones, in that glucose, when injected intravenously, apparently exercises a progressively less beneficial effect on the characteristic hypoglycemic condition which follows the removal of the liver of mammals and cold-blooded vertebrates.
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    Journal of Morphology 41 (1925), S. 239-265 
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    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: This paper reports experiments with Fundulus heteroclitus to modify larval development by means of ultraviolet radiation. Eggs were exposed to radiation at various intervals after fertilization for varying periods of time. The results accord with previous work on fish teratology, and the developmental types obtained are essentially similar to those produced by chemicals, cold, and hybridization. The deviations from normal development occur in the same body regions as do those in other vertebrates whose early development has been modified by the action of radiation (x-rays, radium, etc.).The results of these experiments indicate that there is a non-specificity in susceptibility relations with the production of similar types of monsters for widely different reagents. That these eggs are differentially susceptible to the action of ultraviolet radiation is indicated by the fact that those regions which have the highest metabolic activity when an inhibiting influence is active are the ones most generally affected. Thus modifications of the nervous system, sense organs, circulatory system, tail region, and body axis result, respectively, in the production of varying degrees of cyclopia, inadequate circulation, short, stubby or bent, non-motile tails (some bifid), and anterior twinning.As these modifications may be produced by applying inhibiting influences during the first few minutes after fertilization, it is evident that there is in the egg at this stage some constitutional or physiological basis which determines early differences in susceptibility of its various parts.
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    Journal of Morphology 41 (1926), S. 427-439 
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    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: Webbing of toes or fingers in man is produced by a local arrest of development, causing retention of the normal embryonic webbing. This type of digital fusion involves only the skin, the skeleton being unaffected. The extensor tendons of the toes may sometimes be fused.Webbed digits occur normally in some marsupials, rodents, and insectivores, in a number of lemurs and catarrhines, and in the siamang and gorilla. They also may occur in varying degree in other Primates, notably Hylobates. An analysis of five new pedigrees together with those already published demonstrates that webbing of toes in man may be inherited in either a mendelian or sex-linked manner. In one case this character follows the course of the Y-chromosome.
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    Journal of Morphology 45 (1928) 
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    Notes: Amoeba proteus was raised in a modified and diluted Ringer solution. When the pH of this culture medium became less than 6.0, the normal activities of the amoebae were interfered with; and when a still lower pH was attained, the amoebae died off. The same was true when the pH became greater than 8.0. At neutrality the activities were subnormal, very dark, and rounded. The rate of locomotion of amoebae raised in solutions with a pH less than 7.0 showed a maximum rate of locomotion at pH 6.6, which decreased as the pH changed in either direction, dropping to a very low rate at pH 7.0 and above and also below 6.0. For amoebae raised at a pH above 7.0 the rate was maximum at pH 7.6 and decreased as the pH changed in either direction; it was low at pH 7.0 and below and also above 8.0.On increasing the external osmotic pressure of the medium it was found that the effects caused varied somewhat with the hydrogen-ion concentration. Small increases in osmotic pressure decreased the rate from the normal at pH 6.0 and 8.0, increased it at pH 6.6 and 7.6, and did not affect it at pH 7.0. Osmotic pressures above that produced by M/20 lactose caused locomotion to cease in a short time at all pH values.
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    Journal of Morphology 45 (1928), S. 209-231 
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    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: The highly specialized cranial musculature of the toadfish is characterized by the following features: 1Absence of intermandibularis and branchiomandibularis muscles.2Presence of levator premaxillaris muscle.3Very large branchial chamber, the outer wall of which is formed by seven branchiostegal rays connected by a strong fascia provided with muscles (oblique levators and adductors).4Highly developed masticator muscles (adductor mandibularis and pterygoids).5The rectus abdominis, sternohyoid, and hyohyoid muscles are attached by a median aponeurosis to the hyoid and basibranchial elements and directly to the hypobranchial cartilages; this muscle complex depresses the buccal floor in opposition to the geniohyoid.6The pelvic fins are in the jugular position.7Two narrow muscles connect the cleithrum with the fourth ceratobranchial.8The cranial musculature is obviously adapted to a carnivorous habit and particularly for increasing respiratory capacity under asphyxial conditions.
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    Journal of Morphology 45 (1928), S. 293-398 
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    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: Blindfolded persons walk, run, swim, row, and drive automobiles in clock-spring spiral paths of greater or less regularity when attempting a straightaway. The spirals turn either right or left in one and the same individual, and may do so even in one experiment. But either right or left turns predominate in the great majority of individuals, often to a high degree. The paths show marked individuality, and there is some ground for thinking there exists a correlation between temperamental differences and general character of path.The mechanism which produces the spiral path is not located in the locomotor organs, but in the central nervous system and is probably identical essentially with the spiral mechanism in other motile organisms, all of which move in spiral paths when there are no guiding senses to direct the path. The clock-spring spiral in man is interpreted as the expression in two dimensions of space of a helical spiral mechanism which seems to exist in all motile organisms moving in three dimensions of space and in amebas which move in two dimensions. In a large number of lower organisms the number of body lengths per spiral turn is almost constant, being about 4.5. The smallest regular swimming spirals in man are very close to this value, but the smallest regular walking spirals are somewhat larger. The fundamental spiral mechanism seems to be of molecular dimensions, and there seems to exist a demonstrable locomotor bilateral asymmetry in very nearly, if not quite, all organisms.
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    Journal of Morphology 45 (1928), S. 473-503 
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    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: A detailed study has been made of the anatomy of one of the fingernail shells, and preliminary observations on the life-history have been carried out. In its general organization Sphaerium notatum is very similar to the larger fresh-water lamellibranchs. A gastric shield, crystalline style, and style sac, very similar to those found in the stomach and intestine of Lampsilis, are present. A pair of slender muscles extending from the dorsal side of the body into the gills, and evidently not previously described, have been found. The nervous system consists of the typical three pairs of lamellibranchiate ganglia, with their connectives, accessory ganglia, and nerve fibers. Particular study was given to the statocysts and osphradia, and attention is called to the fact that the function commonly ascribed to the osphradia is incompatible with their position in the roof of the cloacal chamber.S. notatum, like all the Sphaeriidae, is hermaphroditic and viviparous. The gonads are paired racemose glands lying behind and below the stomach. The sperm-producing follicles form the anterior portion of each gonad and are somewhat smaller and more numerous than the ova-producing follicles which form the posterior portion. The young pass through the early stages of development in brood pouches in the gills and are expelled as relatively enormous individuals.Preliminary observations on the life-history indicate that reproduction reaches its height in the summer and that fertilization probably takes place during the late summer and fall.
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    Journal of Morphology 45 (1928), S. 579-597 
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    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: When Menidia eggs are fertilized with Prionotus sperm, the Prionotus chromosomes react in the Menidia cytoplasmic medium just as they do in the cytoplasm of Fundulus eggs. There is lagging, non-disjunction, and elimination of chromosomes during the early cell divisions. The mitotic behavior of the Prionotus sperm in the Menidia egg also resembles the behavior of the sperm of Ctenolabrus in the same medium. This behavior which was expected from what was known concerning the mitotic behavior of the reciprocal crosses between Menidia and Fundulus and between Ctenolabrus and Prionotus and other intercrosses between the members of these two groups is regarded as a function of the physical state of the egg cytoplasm during the division phase of mitosis. This physical character forms the earliest differential factor in the development of these hybrids and shows no correlation with the width of the cross.A comparison of nine teleost crosses, in which both the development and the early mitotic behavior are known, with a rough numerical estimate of the width of the cross brought out the fact that development is most successful in crosses between nearly related species if mitosis is normal and in distantly related crosses if mitosis is abnormal. This indicates that nuclear relationship is also a factor in the development of hybrids.
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    Notes: Virulent hay-infusion cultures of Bacillus pyocyaneus are toxic to pure-line races of three species of paramecia, but these races may acquire a tolerance for this toxic agent. Races with acquired tolerance have been grown for long periods of time in toxic, pure cultures of B. pyocyaneus by means of the daily-isolation culture method, and here the average division rate is as high as, or higher than, in the chance-mixed bacterial cultures in which these protozoa are usually maintained in the laboratory. The tolerance is lost, however, when the paramecia are removed from the toxic cultures and grown for a number of generations in cultures of non-toxic bacteria.The toxic agent that is lethal to paramecía is probably the soluble toxin of B. pyocyaneus. The investigation shows that the agent is soluble and either thermolabile or volatile. It also shows that all deleterious substances, other than the soluble toxin, known to be produced in cultures of this bacillus, are non-lethal to paramecia.Hay-infusion cultures of Bacillus enteritidis were lethal to paramecia. All attempts to develop tolerance in paramecia for the toxic agent in these cultures failed.Under the experimental conditions that prevailed, diphtheria toxin was found to have no appreciable effect upon the division rate or death rate in three species of paramecia.
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  • 74
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    Journal of Morphology 40 (1925), S. 261-297 
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: The parasynaptic union of chromosomes associated with the formation of a karyosphere is demonstrated in the spermatocytes of Phanaeus.The twelve V-shaped leptotene threads are polarized with their apices embedded in one plasmosome-like body, their distal ends in another (primary and secondary caps, respectively), and undergo a conjugation of the parasynaptic type. The distal ends of the chromosomes are freed from their attachment in the secondary cap. The six pachytene loops retain their polarized configuration.The basichromatin of the pachytene chromosomes appears ultimately to be withdrawn to form the karyosphere comprising six chromatic bodies within an oxychromatic «plasmosome,» the latter probably derived from the primary cap. The two caps are believed to arise from the chromosomes. The primary cap apparently becomes incorporated again in the chromosomes; the secondary cap, together with linin remnants of the pachytene chromosomes, disintegrates in the nucleus as residual chromatin.In the dissolution of the karyosphere six ring-shaped tetrads emerge arranged in a temporarily connected chain, giving under certain conditions, the misleading impression of twelve components arranged end to end. The entire content of the karyosphere appears to be employed in the formation of the chromosomes; no visible plasmosome remains.
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  • 75
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    Journal of Morphology 41 (1926), S. 441-546 
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: Embryological study of bullfrog tadpoles collected from various parts of the United States has shown the existence of local races which differ markedly in regard to the time of occurrence and character of the developmental processes involved in the formation of the definitive testis of the male individuals. Those races in which the gonads of the two sexes are easily distinguished in early larval stages are called differentiated. Other local races show a peculiar gonadic development chiefly affecting the males, the definitive testis sometimes not appearing until near the end of the second year of larval life. Such races are called undifferentiated, because the morphological features of the definitive testes are not established until late. The larvae first develop a peculiar gonad (progonad) which later degenerates and is replaced by the definitive testis. All male animals of the undifferentiated strains exhibit the gonad cycle.The progonad varies among the local frog races in regard to the length of persistence and degree of differentiation attained before undergoing degeneration. Its germ cells may exhibit a typical male maturation cycle ending in degeneration, or the cells may differentiate along both male and female lines or remain sexually neutral.The development and differentiation of the progonad in the various races are described and a detailed account given of the origin of the definitive testis. The problems of sex differentiation and continuity of the Keimbahn in anurans are discussed.
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  • 76
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    Notes: The primordial germ cells of urodeles and anurans can occupy comparable positions in the embryo only in very early stages of development, if at all. When first recognizable as reproductive elements, their situation in the two amphibian orders is quite strikingly different.The germ cells first become recognizable in urodeles in the medial edge of the lateral mesoderm; there is no evidence that their position previous to this time is other than mesodermal. In the anura they are entodermal in association during early development; they are finally separated from the dorsal portion of the roof of the archenteron to form a single axial germ-cell cord. No amphibian species studied showed a mode of origin different from that characteristic of its order.The so-called migration of the amphibian germ cells to their definitive situation is interpreted as the result of growth shiftings of related parts. Germ cells do not migrate independently through the tissues. Aberrant or ectopic cells for the most part result from failures or faulty correlations of growth processes. Certain aberrant cells of the caudal portion of the body in urodeles indicate the inclusion of sex elements in the ventral as well as in the lateral mesoderm.
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  • 77
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    Notes: The musculature of the ophidian head is a fairly complex structure, due to the specialization of the skull and the peculiar movements and motions made possible by the high degree of streptostylism.This musculature has been derived from the lacertilian type by a splitting and a shifting of the original elemental muscle masses of this group. Most of the muscles are clearly homologous with those of the Lacertilia. Some cannot be homologized by a study of the mature forms.The greatest differences lie in the separation of the muscle masses in the ophidia, as compared with the undivided masses in the Lacertilia. Since the jaw movements of the Lacertilia are rather simple, there is no need for any subdivision or splitting of the jaw muscles, but with the complex movements of the ophidia this becomes necessary.A few of the ophidian muscles appear to be neomorphs, as no key to their origin could be determined by a comparison with lacertilians.
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  • 78
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    Journal of Morphology 41 (1926) 
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  • 79
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    Journal of Morphology 41 (1926), S. 333-345 
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    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: In a leech infesting the Alaskan codfish germinal masses in the ovary proliferate secondary groups, comprising about forty cells in which a follicle and central supporting cell early differentiate. Active division results in approximately 500 cells which apparently develop ductules extending to a point on the surface of the egg. Granules of unknown origin then appear in each nurse cell, and are drawn down the ductules into the egg which can now be distinguished. Reasons are given for the belief that the nutritive material is drained from the nurse cells by amoeboid activity of the egg. In early stages the nutritive mateiral forms a loose reticulum which gradually becomes transformed into a more extensive network, persisting until the maturation divisions. In this latest period the follicle and nurse cells, which become shrunken as the ovum enlarges, usually are stripped off and soon disintegrate.
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  • 80
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    Journal of Morphology 41 (1926), S. 547-579 
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    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
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    Notes: The pelvic fins of the ancestors of the Chondrosteoidei possessed a metameric musculature and their skeleton consisted of a large number of metamerically arranged cartilaginous fin-rays, to which were attached osseous lepidotrichia. Evolution has involved the concrescence of separate elements to form the basal cartilage, the proximal end of which forms the girdle of the fin; the loss of a number of the fin-rays, and the atrophy of distal elements of the rays. The adult Chondrosteoidei have retained the primitive fin structure which characterized the elasmobranchs of the Palaeozoic period and which has disappeared in recent forms.
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  • 81
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    Journal of Morphology 42 (1926), S. 143-195 
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    Notes: On the basis of experimental study and observations on the morphology of the legs of spiders, P. Friedrich described a cutting device within the trochanter which would sever that appendage from the body when the leg was stimulated by injury.A reinvestigation of the problem yielded entirely contrary results. Experiments calculated to induce spontaneous amputation through an automatic reflex in the leg were negative on scorpions, harvestmen, and more than a dozen species of spiders. A detailed morphological study of the skeleton and musculature of the arachnid leg showed that no autotomizing device exists, either in the skeleton or in the arrangement of muscles (as is usually supposed). In all species studied, except the scorpion, severance of the leg from the body occurs most readily at some given point. The point at which severance readily occurs is directly correlated with a definite structural weakness in the skeleton and musculature. The spider itself removes an injured leg by grasping the stump with its mouth-parts. No such injured stump falls off spontaneously or without the application of tension. Scorpions do not autotomize appendages under any stimulation, nor do they show any anatomical weakness in the leg skeleton or musculature.Autotomy as an automatic reflex does not exist in the Arachnida.
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  • 82
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    Notes: Sixteen species of the genus Scyllium are here considered and arranged in groups according to the accessory structures present on the claspers as follows:1Canicula, sufflans, ventriosum.2Catulus, stellare, capense, variegatum (var. pantherinus), umbratile.3Burgerii, hispida, bivium, anale, natalense, edwardsii.4Marmoratum, laticeps.The structure of the wall of the oviduct and vagina is demonstrated, and it is shown that the epithelium of both is at first columnar, then ciliated in immature specimens; at maturity that of the vagina further undergoes by transitions a change to stratified. The walls are highly vascular, but contain no special glands.
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  • 83
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    Notes: Amoeba responds to a mechanical shock by a cessation of movement which occurs shortly after the application of the stimulus. The length of the reaction time, the period intervening between application of stimulus and the response, varies inversely with the magnitude of the shock. After stopping Amoeba remains quiescent for a short time, and the length of this period of quiescence varies directly with the magnitude of the shock. A certain amount of time must elapse after a reaction before another can be obtained; during this time the animal reverts to the physiological state which existed prior to the first shock.Partial recovery from the effects of a shock is manifested by a reaction time that is longer than after complete recovery, and a period of quiescence which is shorter. A shock which in itself is too slight to cause a cessation of movement may result in the lack of a response to a heavier one which follows immediately after it, although under other conditions the second shock would have called forth a reaction. If the second shock, however, is made sufficiently heavy, it will bring about a response, despite the effects of the first. This is what would be expected if the reactions take place in accordance with the Weber-Foechner law.
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  • 84
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    Journal of Morphology 42 (1926), S. 523-560 
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    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: The different kinds of scales characteristic of the adult sturgeon are described and the facts of ontogenesis which throw light on the history of these structures are presented.The scales of Acipenser are exclusively mesenchymatous and therefore are not morphologically comparable with the placoid scales of elasmobranchs. Salensky ('80) drew erroneous conclusions as a result of failure to study the earlier stages of ontogenesis. Goodrich ('03) has correctly described the ontogenesis of the lepidotrichia.The original form of ganoid scale was that of an elongated rhomb with a longitudinal crest on its external surface. The various forms of scales of the adult sturgeon have been produced by the differentiation of such a scale by change in size, shape, and the fusion of the different elements.The conclusions are extended to the entire family of Acipenseridae.
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  • 85
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    Notes: The lips of the animal are modified in relation to the act of passing seeds into the sac. The cheek-sacs are invaginations of the buccal mucosa, and their development as diverticula of the vestibulum oris is associated with the establishment of extrinsic muscles, derived from the platysma. The sac is invested by a coat of striated muscle. The epithelial lining of the sac attains a degree of complexity comparable to the epidermis of the skin, except that a stratum lucidum and stratum granulosum are not developed. No glands are developed in the mucous membrane of the sac.
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  • 86
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    Notes: Three groups of pure lines of diverse clones of Didinium nasutum were maintained in isolation cultures for 778, 786, and 457 generations, respectively, without exhibiting any decrease in fission rate or any increase in encystment rate or death rate. These lines were supplied with Paramecium caudatum in such numbers that a surplus of food was present at all times.Three other groups of lines of the same clones were established simultaneously and cultured in parallel with the preceding groups, but the food of each of these lines was limited to nine paramecia per line daily. The fission rate of these lines fell to zero and the encystment rate increased to 100 per cent after 155, 165, and 113 generations of culture, respectively. The death rate increased appreciably in these lines prior to encystment.Other groups of pure lines were cultured on a diet limited to six paramecia per line daily. These lines encysted after approximately fifteen generations of culture.This evidence indicates that there is nothing in the nature of a definite life-cycle in Didinium and that diminished vitality and encystment do not result from the passage of generations, but from inadequate and unfavorable cultural conditions-specifically, from in-sufficient food. It shows further that it is possible to induce cycles with reference to encystment in Didinium by limiting the food supply and to vary the length of the cycles by varying the quantity of food.
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  • 87
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    Notes: Chlamydoselachus resembles the Holocephali in possessing no siphon, but a cavity in the proximal portion of the clasper. The cartilages, musculature, and venous sinuses of the clasper are considered. An older specimen of Echinorhinus is proved to have a spine on a soft papilla; Scymnus has no spine; both have the general features of the Spinacidae. Two species of Cestracion are compared with C. philippi. Mustelus lunulatus lacks the pera and pseudosiphon of M. vulgaris. Dicerobatis has a peculiar scaphus, and the claspers end in a fimbriated manner. Pteroplatea resembles Trygon and Benthobatis and Astrape are both like Torpedo.The species are listed below.
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  • 88
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    Journal of Morphology 40 (1925), S. 1-109 
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    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
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    Notes: Much more information than is available at present must be obtained before the phylogeny of the muscular system in the Teleostei can be worked out satisfactorily. As a step toward the solution of this problem, the present study gives a detailed description of twenty cranial muscles in a number of species belonging to three groups of cypriniform fishes: the Cyprinoids, Cobitoids, and Siluroids.Particular attention is given to the morphological relations of the following muscles: adductor mandibulae, geniohyoideus, levator arcus branchialis, adductor arcus palatini, retractor branchialis dorsalis, interarcualis dorsalis and the trapezius.Comparison is made between corresponding muscles in different members of the three groups of fishes, and various homologies are pointed out between muscles in cypriniform and those in other fishes, especially Amia, Scomber, Perca and Esox.
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  • 89
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    Journal of Morphology 44 (1927), S. 89-115 
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    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: The investigation is based upon hemal nodes of dog, man, and sheep. The material can be arranged in a regressive series leading from a typical lymph node, except for the occurrence of blood in parenchyma and sinuses, to a lymphoid structure at a late stage of involution. These structures uniformly lack lymphatics. There is no evidence of direct luminal connection between the blood-vascular supply and the sinuses. The observation that certain cervical and subcutaneous lymph nodes of the rabbit undergo a myeloid metaplasia following atrophy and disjunction of their lymphatics is used as an explanatory key of hemal nodes. According to our view, hemal nodes represent stages in the involution of transient lymph nodes. Disjunction of the lymphatics leaves the sinuses filled with entrapped lymphocytes. These differentiate into erythrocytes. These red blood cells may disintegrate and pass into solution or be removed either by giant cells or mononuclear phagocytes. Late stages in this process are represented by small irregular masses of lymphocytes, with wide sinuses practically free of blood.
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  • 90
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    Journal of Morphology 44 (1927), S. 217-264 
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    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: A description is given of the cytoplasmic alterations in the ovarian egg of Limulus polyphemus leading to the formation of yolk. The nucleolus is found to arise by the confluence of substance which passes from the cytosome into the nucleus, and it is suggested that the chondriosomes, and possibly also the dictyosomes, are derived from an excess of this substance which accumulates in the cytosome. Chondriosomes and dictyosomes are not present in the oogonia, but appear first in oocytes after the formation of the nucleolus is completed.During oogenesis the nucleolus is very active and the greater part of its substance is passed back to the cytosome. By the application of the method of Bell and Doisy for the determination of phosphate in body fluids, the nucleolus is found to be richer in phosphorus than are the other constituents of the cell. The nucleolar emissions effect the transport of phosphorus from the nucleus to the cytosome, where it is used in the synthesis of yolk. The definitive yolk arises by the interaction of nucleolar emissions, chondriosomes, dictyosomes, and ground cytoplasm.
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  • 91
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    Journal of Morphology 44 (1927), S. 341-361 
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    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: Conjugating individuals of Metopus sigmoides fuse at the anterior end, the pair presenting the appearance of an inverted letter U. The micronucleus of each conjugant by two successive divisions forms four micronuclei. Three of each four degenerate and the fourth by division forms the pronuclei. Cytoplasm and pronuclei from one conjugant pass over into the other, leaving the old macronucleus and a minimum of cytoplasm behind in the shrunken pellicle of the smaller conjugant, which then separates from the larger one. In the larger exconjugant two pronuclei fuse, forming the functional synkaryon; the two residual pronuclei degenerate and disappear. The synkaryon divides. One of the daughter nuclei condenses into the new micronucleus, the other grows into the new macronucleus. The old macronucleus liquefies and is absorbed. The larger exconjugant, after losing its cilia, secretes a cyst wall about itself and becomes dormant. The whole process requires at least six days for its consummation.
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  • 92
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    Notes: In conjugation fusion occurs along the entire oral surfaces of the proboscides of Dileptus gigas. Two size-reducing divisions occur in rapid succession immediately preceding conjugation. Only one of the many micronuclei takes part in the process of nuclear reorganization. All other chromatic material is massed at this time in the posterior portions of the conjugants. The pronuclei are derived from the single active micronucleus, and interchange occurs immediately preceding the separation of the mating individuals. The fertilization nucleus divides to form two nuclei of diverse size. The smaller one produces thirty-two or sixty-four micronuclei, while the larger one divides to produce a like number of macronuclei, each of which finally breaks up into many chromatic granules which form the numerous densely staining nuclear derivatives which are characteristic of the vegetative stage of Dileptus gigas.In the early stages of this reorganization process specimens are frequently found with from two to eight distinct nuclei often arranged in a series as in a beaded nucleus. This condition probably explains the frequent references in literature regarding such a nuclear condition in Dileptus.Dileptus gigas has, accordingly, in the vegetative stage, a multinucleate condition with reference to the micronucleus and a fragmented or distributed condition with reference to the macronucleus.
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  • 93
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    Notes: By the use of a satisfactory technique, excellently preserved spermatogenetic tissue was had both for Rattus rattus and Rattus norvegicus. The careful examination of twelve spermatogonial cells of the former species and of twenty in the latter species shows that R. rattus has forty diploid chromosomes and R. norvegicus, forty-two. A careful examination of the haploid cells of both species, both in the first and in the second spermatocyte divisions, confirms the diploid determinations.Both species have an unequal pair in the spermatogonial divisions and the finding of a similar unequal pair in the first spermatocyte division constitutes the evidence for an X-Y mechanism in each. A comparison of the morphology of the first spermatocyte tetrads in the two species reveals the presence of a large K-shaped chromosome in R. norvegicus which is not present in R. rattus. Furthermore, a comparison of the X-Y complex in both the spermatogonial and first spermatocyte divisions shows that these are morphologically different in the two species, the Y in particular being markedly dissimilar in size. A short discussion as to the bearing of these findings on the questions of the origins of the two species and their known intersterility is presented. The marked similarity of the tetrads of the black rat to those described for the mouse is noted.
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  • 94
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  • 95
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    Journal of Morphology 44 (1927), S. 29-87 
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    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: The anlage of the abducens musculature appears first at 24-25 somites as a condensation situated dorsal to the mandibular arch.The anlage of the superior oblique grows forward from a mesodermal condensation situated in the maxillomandibular region, termed for convenience the maxillomandibular condensation. This last consists of three parts: (1) the anlage of the superior oblique: (2) the anlage of the abducens musculature, and, (3) an intermediate region.The intermediate portion of the maxillomandibular mass forms a condensation with which the anlage of the abducens musculature fuses. Its fate is, therefore, similar to that of the so-called ‘muscle E’ of elasmobranchs, which has been described as fusing with the lateral rectus. How much muscle is formed from the intermediate condensation in the chick has not been determined.The development of the pyramidalis and quadratus nictitans muscles, derivatives of the abducens complex, is described.The premandibular head cavities are replaced by solid mesodermal condensations, on the surface of which the anlagen of the oculomotor muscles appear. The premandibular mass expands laterally and anteriorly over the bulbus, carrying the oculomotor muscles to their respective positions on the bulbus.Portions of the premandibular and maxillomandibular condensations not involved in eye-muscle formation take part in the formation of choroid and sclera.The growth shiftings of the eye muscles are analyzed. The order of their appearance is commented upon.
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  • 96
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    Journal of Morphology 44 (1927), S. 127-216 
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    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: This study represents the first critical investigation on the development of the embryonic skull of the porcupine. A complete series of stages makes it possible to trace the developing chondrocranium from its first formation in precartilage to its later transformation into cartilage bone. Concurrent with this growth is the investment of the cartilaginous cranium by membrane bone.The very primitive nature of the chondrocranium offers an excellent opportunity to discuss the existing problems of the embryonic skull from a new angle. Evidence is presented in support of the assumption that the ala temporalis is the homologue of the cynodont epipterygoid. The lamina parietalis develops from a single chondrifying center, thus producing a different arrangement of parietal elements from that found in most mammals. New evidence as to the relationship of the dens epistrophei and basal plate is presented. The position of the internal carotid artery on entering the cranium is different from the condition found in most mammals and throws new light on the interpretation of surrounding structures. The presence of a structure comparable with the crista longitudinalis of Lacerta shows close affinity to the solum nasi of more primitive forms.The great specialization of the face is seen in the early and rapid growth of the membrane bones. The chondrocranium is long persistent and cartilage bone appears late in embryonic life.
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    Journal of Morphology 44 (1927), S. 417-465 
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    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: Observations indicate that this Balantidium from the guinea-pig is Balantidium coli, the form found in the pig and man. The lengths and breadths of this Balantidium and the ratios of length to breadth are very close to the measurements and ratios given by McDonald for B. coli. When plotted, the body lengths of the guinea-pig parasites appear in two groups, the smaller individuals being the exconjugants. Many of these exconjugants resemble Neiva's B. caviae. The structure of the Balantidium from the guinea-pig is essentially identical with that of B. coli as given by McDonald.Fission and conjugation of this ciliate follow the general course found in a number of other ciliates. During fission the micronucleus divides and the daughter micronuclei migrate to each end of the macronucleus before the latter divides. In conjugation there are two divisions of the micronucleus, one of these nuclei dividing to form the pronuclei. Pronuclear exchange and fusion are followed by a heteropolar division of the synkaryon, resulting in the formation of the new macronuclear and micronuclear anlagen.The parasite was found in the intestinal tissue of the host. No reproductive stages were found in the cysts. New hosts are invaded through contamination of the food and drink with the cysts.
    Additional Material: 1 Ill.
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  • 99
    Electronic Resource
    Electronic Resource
    New York, NY : Wiley-Blackwell
    Journal of Morphology 42 (1926), S. 23-81 
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: The flagellate, Tetramitus rostratus Perty, appeared in cultures of certain amoebae obtained from the coecum of rats. In a typical life-cycle a cyst, planted in an appropriate medium, gives rise to an amoeba which may divide a number of times, but eventually some of the amoebae transform into flagellates identical with Tetramitus rostratus. These divide frequently through several days, sometimes for weeks or months, and then transform back to amoebae which become encysted.During excystment the smooth cyst wall dissolves. Usually both the amoeboid and flagellate phases pass into a “gel” state during division. A “gel” state sometimes occurs during transformation. The time required for transformations varies from a few minutes to several hours.Many culture media and methods have been tested. In certain cultures the flagellate phase was prolonged for weeks or months. These cultures were characterized by: 1) great variation in size, from minute “dwarfs” to oversized “monsters”; 2) frequent multiple fission; 3) pairing and fusion, and, 4) some evidence for the origin of secondary nuclei from chromidia. In cases of pairing and fusion, the process of maturation and union of nuclei could not be definitely proved, although suggested by the observations.The flagellate phase is more probably the “adult” phase because of its complex organization and possible sexual phenomena. This case is considered an extreme for this type amoeba-flagellate transformation.
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  • 100
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: In the blastula the region of accelerated cell division is on the ventral side of the egg, nearly opposite the site of the future beginning blastopore. The ventral wall of the blastocoele is thicker than the dorsal. In the very early gastrula a new region of accelerated cell division appears in the vicinity of the dorsal lip of the blastopore.A downward movement of material comprising the marginal zone of micromeres and the portion of the wall of the blastocoele immediately above it occurs during all the later blastula stages and continues until this material is carried below the level of the equator and involved in the process of gastrulation. On the dorsal side of the egg, this movement is more rapid than on the ventral side.In the late blastula stage there are evidences of growth in the region of smaller micromeres. In the very late blastula, a vertical groove appears at the dorsal margin of the floor of the blastocoele; this groove is believed to indicate the operation of factors concerned with gastrulation.In connection with the first nuclear division, evidences of cytoplasmic activity leading to the formation of the first cleavage furrow are described. As the blastomeres become smaller, progressive changes take place in the distribution of their cytoplasm.
    Additional Material: 35 Ill.
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