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  • Cell & Developmental Biology  (172)
  • Pflanzenschädling  (17)
  • Deutschland  (13)
  • 1925-1929
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  • 1
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    Friedr. Vieweg & Sohn, Braunschweig
    In:  SUB Göttingen | 8 GEOGR PHYS 203
    Publication Date: 2024-04-30
    Description: Dieser Band enthält 72 Beiträge zu Themengebieten der Physik der festen Erde, des magnetischen und elektrischen Felds der Erde, der Physik der Atmosphäre sowie der Angewandten Geophysik, veröffentlicht durch die Deutsche Geophysikalische Gesellschaft in den Jahren 1928.
    Description: 〈html〉 〈body〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0004/LOG_0004.pdf"〉Titelseite〈/a〉〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0004/LOG_0005.pdf"〉Gezeitenerscheinungen in der Atmosphäre〈/a〉〈br〉(Bartels, J.)〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0004/LOG_0006.pdf"〉Erdmagnetische Säkularvariation und die Orientation alter Kultbauwerke〈/a〉〈br〉(Wehner, H.)〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0004/LOG_0007.pdf"〉Über die Tiefenwirkung bei geoelektrischen Potentiallinienmethoden〈/a〉〈br〉(Hummel, J. N.)〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0004/LOG_0008.pdf"〉Überblick über den Gang der magnetischen Vermessung der Ostsee〈/a〉〈br〉(v. Gernet, A.)〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0004/LOG_0009.pdf"〉Die Wirkung der Kontinente und Ozeane auf die Differenz 〈i〉B – A〈/i〉 der Hauptträgheitsmomente der Erde im Äquator〈/a〉〈br〉(Gutenberg, B.)〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0004/LOG_0011.pdf"〉Bemerkungen zu H. v. Iherings Kritik der Theorien der Kontinentverschiebungen und der Polwanderungen〈/a〉〈br〉(Wegener, A.)〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0004/LOG_0012.pdf"〉Berichtigung〈/a〉〈br〉(Jung, K.)〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0004/LOG_0013.pdf"〉Illustration〈/a〉〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0004/LOG_0014.pdf"〉Über die Polhöhenschwankungen infolge der Lorentz-Kontraktion der Erde〈/a〉〈br〉(Courvoisier, L.)〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0004/LOG_0015.pdf"〉Zum Uhrvergleich auf drahtlosem Wege nach der Koinzidenzhörmethode〈/a〉〈br〉(Martin, H.)〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0004/LOG_0016.pdf"〉Physikalische Grundlagen einer neuen geoelektrischen Aufschlußmethode〈/a〉〈br〉(Hummel, J. N.)〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0004/LOG_0017.pdf"〉Untersuchung der Potentialverteilung für einen speziellen Fall im Hinblick auf geoelektrische Potentiallinienverfahren〈/a〉〈br〉(Hummel, J. N.)〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0004/LOG_0018.pdf"〉Mächtigkeitsbestimmung von Deckschichten über Spalten durch Radioaktivitätsmessungen〈/a〉〈br〉(Koenigsberger, J.)〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0004/LOG_0019.pdf"〉Zur Frage der regionalen, magnetischen Anomalien Deutschlands, insbesondere derjenigen Norddeutschlands〈/a〉〈br〉(Reich, H.)〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0004/LOG_0021.pdf"〉Untersuchungen über die seismische Bodenunruhe kurzer Periode〈/a〉〈br〉(Schneider, W.)〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0004/LOG_0022.pdf"〉Zur Theorie elektrischer Bodenforschung〈/a〉〈br〉(Heine, W.)〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0004/LOG_0023.pdf"〉Emil Wiechert †〈/a〉〈br〉(Angenheister, G.)〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0004/LOG_0024.pdf"〉Die topographische Reduktion bei Drehwagenbeobachtungen〈/a〉〈br〉(Numerov, B.)〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0004/LOG_0025.pdf"〉Angewandte Seismik (Zusammenfassender Bericht über Arbeiten von 1921 bis 1928)〈/a〉〈br〉(v. Schmidt, O.)〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0004/LOG_0027.pdf"〉Le problème des microséismes à groupes〈/a〉〈br〉(Gherzi, E.)〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0004/LOG_0028.pdf"〉Zur Empfindlichkeitsbestimmung von magnetischen Variometern und zur Eichung der magnetischen Felder von Spulen〈/a〉〈br〉(Koenigsberger, J.)〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0004/LOG_0029.pdf"〉Die Schrumpfungsgeschwindigkeit des Erdradius aus astronomischen Beobachtungen〈/a〉〈br〉(Meyermann, B.)〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0004/LOG_0030.pdf"〉Über eine Verbindung zwischen den mondentägigen und den sonnentägigen Variationen der magnetischen Deklination〈/a〉〈br〉(Egedal, J.)〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0004/LOG_0031.pdf"〉Die Zone der anormalen Hörbarkeit im kleinen〈/a〉〈br〉(Hiller, W.)〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0004/LOG_0032.pdf"〉Mitteilungen〈/a〉〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0004/LOG_0033.pdf"〉Ein graphisches Verfahren für Drehwagenmessungen zur Berechnung der Geländewirkung und der Wirkung beliebig gestalteter Massenkörper〈/a〉〈br〉(Haalck, H.)〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0004/LOG_0035.pdf"〉Beiträge zur geoelektrischen Methode〈/a〉〈br〉(Hummel, J. N.)〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0004/LOG_0036.pdf"〉Zum Uhrvergleich auf drahtlosem Wege nach der Koinzidenzhörmethode〈/a〉〈br〉(Mahnkopf, H.)〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0004/LOG_0037.pdf"〉Berichtigung〈/a〉〈br〉(Meyermann, B.)〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0004/LOG_0038.pdf"〉Zur Frage nach der Ursache von lokalen gravimetrischen und erdmagnetischen Störungen und ihre wechselseitigen Beziehungen〈/a〉〈br〉(Haalck, H.)〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0004/LOG_0040.pdf"〉Gemeinschaftliche Arbeit zwischen Seismologen und Baufachmann zur Verringerung von Erdbebenschäden〈/a〉〈br〉(Briske, R.)〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0004/LOG_0042.pdf"〉Feldapparatur zur Registrierung von Zeitzeichen〈/a〉〈br〉(Köhler, R.)〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0004/LOG_0043.pdf"〉Über die Schmidtsche Methode der Bestimmung der Parameter von Stabmagneten〈/a〉〈br〉(Bock, R.)〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0004/LOG_0046.pdf"〉Referate der Vorträge auf der Tagung der Deutschen Geophysikalischen Gesellschaft in Hamburg vom 19. bis 21. September 1928〈/a〉〈br〉(Koenigsberger, J.)〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0004/LOG_0048.pdf"〉Die Seismizität der Ozeane und Kontinente〈/a〉〈br〉(Tams, E.)〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0004/LOG_0049.pdf"〉Bodenunruhe durch Brandung und durch Frost〈/a〉〈br〉(Gutenberg, B.)〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0004/LOG_0050.pdf"〉Beitrag zur Schallausbreitung in der Atmospähre〈/a〉〈br〉(Kölzer, J.)〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0004/LOG_0051.pdf"〉Das Magnetfeld einer elektrischen Strömung im anisotropen leitenden Halbraum〈/a〉〈br〉(Müller, M.)〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0004/LOG_0052.pdf"〉Die geführten elastischen Zweimittel-Wellen〈/a〉〈br〉(Uller, K.)〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0004/LOG_0053.pdf"〉Vom Jahre 1922 an im südlichen Norwegen aufgenommene Nordlichtphotogramme〈/a〉〈br〉(Störmer, C.)〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0004/LOG_0055.pdf"〉Zur Frage nach der Ursache von lokalen gravimetrischen und erdmagnetischen Störungen und ihre wechselseitigen Beziehungen〈/a〉〈br〉(Haalck, H.)〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0004/LOG_0057.pdf"〉Vorträge, gehalten auf der Tagung der Deutschen Geophysikalischen Gesellschaft vom 19. bis 21. September 1928〈/a〉〈br〉(Seilkopf, H.)〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0004/LOG_0060.pdf"〉Statistische Mechanik der Atmosphäre〈/a〉〈br〉(Baur, F.)〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0004/LOG_0061.pdf"〉Das Schwadorfer Beben vom 8. Oktober 1927〈/a〉〈br〉(Conrad, V.)〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0004/LOG_0062.pdf"〉Das Periodogramm der internationalen erdmagnetischen Charakterzahlen〈/a〉〈br〉(Wenzel Pollak, L.)〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0004/LOG_0064.pdf"〉Der Stand der erdmagnetischen Forschung〈/a〉〈br〉(Schmidt, A.)〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0004/LOG_0065.pdf"〉Magnetische Anomalien im westlichen Mecklenburg〈/a〉〈br〉(Schuh, F.)〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0004/LOG_0066.pdf"〉Bemerkungen zur numerischen und graphischen Behandlung der Krümmungsgröße〈/a〉〈br〉(Jung, K.)〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0004/LOG_0067.pdf"〉Der Wasserhaushalt der Antarktis in der Eiszeit〈/a〉〈br〉(Meinardus, W.)〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0004/LOG_0068.pdf"〉Übersicht über Neuerscheinungen〈/a〉〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0004/LOG_0069.pdf"〉Vortrage, gehalten auf der Tagung der Deutschen Geophysikalischen Gesellschaft vom 19. bis 21. September 1928〈/a〉〈br〉(Tams, E.)〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0004/LOG_0071.pdf"〉Über kartographische Darstellung der Seismizität〈/a〉〈br〉(Renquist, H.)〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0004/LOG_0072.pdf"〉Ergebnisse von Pilotaufstiegen im Gebiete von Island〈/a〉〈br〉(Georgi, J.)〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0004/LOG_0073.pdf"〉Referat über die Polarfront- und Äquatorialfronttheorien〈/a〉〈br〉(Stüve, G.)〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0004/LOG_0074.pdf"〉Die Messung der Horizontal- und der Vertikalintensität mit dem Magnetron〈/a〉〈br〉(Rössiger, M.)〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0004/LOG_0075.pdf"〉Untersuchungen über die lokalen Schwankungen des Erdpotentials〈/a〉〈br〉(Stoppel, R.)〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0004/LOG_0076.pdf"〉Klima und Klimatafel von Hamburg〈/a〉〈br〉(Perlewitz, P.)〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0004/LOG_0077.pdf"〉Neue Ergebnisse über die Struktur des Windes (Vorläufige Mitteilung)〈/a〉〈br〉(Schmidt, W.)〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0004/LOG_0079.pdf"〉Lokale und regionale magnetische Anomalien in Schleswig-Holstein〈/a〉〈br〉(Reich, H.)〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0004/LOG_0080.pdf"〉Die optische Station in Simferopol〈/a〉〈br〉(Tichanowsky, J.)〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0004/LOG_0081.pdf"〉Das Strömungssystem der Luft über dem tropischen Atlantischen Ozean nach den Höhenwindmessungen der Meteor-Expedition〈/a〉〈br〉(Kuhlbrodt, E.)〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0004/LOG_0082.pdf"〉Ergebnisse und Aufgaben der meteorologischen Strahlungsmessungen〈/a〉〈br〉(Süring, R.)〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0004/LOG_0083.pdf"〉Ergebnisse von Drehwaagemessungen in Schlewig-Holstein〈/a〉〈br〉(Jung, K.)〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0004/LOG_0085.pdf"〉Aufsätze〈/a〉〈br〉(Lotze, F., Brockamp, B., Haalck, H., Myrbach, O., Whipple, Cabannes, J., Dufay, J., Gherzi, E., Pochettino, A., Rostagni, A.)〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0004/LOG_0096.pdf"〉Mitteilungen〈/a〉〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0004/LOG_0097.pdf"〉Autorenverzeichnis〈/a〉〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0004/LOG_0098.pdf"〉Sachverzeichnis〈/a〉〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0004/LOG_0099.pdf"〉Literaturverzeichnis〈/a〉〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0004/LOG_0100.pdf"〉Geophysikalische Berichte〈/a〉〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN101433392X_0004/LOG_0101.pdf"〉Register der Goephysikalische Berichte〈/a〉〈/li〉 〈/body〉 〈/html〉
    Description: research
    Description: DGG, DFG, SUB Göttingen
    Keywords: ddc:550 ; Physische Geografie ; Atmosphäre ; Aurora ; Deutschland ; Elektromagnetismus ; Erdbeben ; Geoelektrik ; Geomagnetismus ; Gravimetrie ; Gravitation ; Island ; Klima ; Meteorologie ; Norwegen ; Polwanderung ; Seismik ; Tektonik ; Zeit
    Language: German , English , French
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  • 2
    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
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  • 3
    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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  • 4
    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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  • 5
    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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  • 6
    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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    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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  • 8
    Electronic Resource
    Electronic Resource
    New York, NY : Wiley-Blackwell
    Journal of Morphology 42 (1926) 
    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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  • 9
    Electronic Resource
    Electronic Resource
    New York, NY : Wiley-Blackwell
    Journal of Morphology 42 (1926), S. 111-141 
    ISSN: 0362-2525
    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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  • 10
    Electronic Resource
    Electronic Resource
    New York, NY : Wiley-Blackwell
    Journal of Morphology 42 (1926), S. 83-109 
    ISSN: 0362-2525
    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.
    Additional Material: 2 Tab.
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