ALBERT

Description: The incidence of Proteocephalus filicollis in Pungitius pungitius, Gasterosteus aculeatus f. hemigymnus and Gasterosteus aculeatus f. trachurus has been studied. It is very low in both forms of Gasterosteus, but 16% of Pungitius was infected. The monthly examination of minimally 27 and maximally 223 Pungitius pungitius indicates that an annual cycle exists neither in the incidence nor in genital development. It seems probable that Proteocephalus filicollis in Pungitius pungitius is less affected by low temperatures than worms of the same species in Gasterosteus aculeatus.\nReference is made to intercurrent helminth infections.

Description: Epiphytic or usually terrestrial ferns with a short fleshy rhizome bearing only one or a few, mostly fleshy, leaves, these erect, petiolate, continuous with the rhizome, the lamina usually divided into a sterile and a stalked fertile portion; veins free or reticulate. Sporangia with a wall composed of several layers of cells, opening with a slit, containing numerous trilete thick-walled subspherical spores of one kind. Four genera, two monotypic, the others with about 60 species of almost world-wide distribution.

Description: The examination of two aberrant Pteropods collected during a trip with the whale factory-ship \xe2\x80\x9dm.s. Willem Barendsz\xe2\x80\x9d led to the conclusion that they were animals in a resting stage. The histology and the anatomy of the totally aberrant soft parts was discussed. The shells of the specimens indicate that these animals are the species Clio antarctica Dall, 1908. One aberrant specimen belonging to the species Clio sulcata (Pfeffer, 1879), collected during the same trip with the whale factory-ship, was examined and it shows that this animal was in a stage between the resting stage and the normal, active, stage. Three specimens of the species Clio pyramidata (Linnaeus, 1767, forma lanceolata (Lesueur, 1813), collected by the Texas and the Dana expedition, were studied as they showed the same aberrations from the normal full grown form as the other three animals previously mentioned. It was clear that the three specimens of the form lanceolata were also in a resting stage and their anatomy and histology were identical with those of the aberrant animals of the species Clio antarctica Dall, 1908.\nThe resting stage seems to have developed from a more specialized stage, as a great store of reserve food was present, while the intestinal duct was not functional and, moreover, the gonad was active.\nThe relation and the distribution of the species Clio pyramidata Linnaeus, 1767, Clio sulcata (Pfeffer, 1879), Clio antarctica Dall, 1908 and Clio martensii (Pfeffer, 1880) was studied and it seems better to consider these species as belonging to one polytypic species and, therefore, as synonymous with Clio pyramidata Linnaeus, 1767. It may be very well possible that Proclio subteres Hubendick, 1951 also belongs to the species Clio pyramidata Linnaeus, 1767. And if that is the case, Proclio subteres Hubendick, 1951 is in all probability synonymous with Clio pyramidata Linnaeus, 1767 forma antarctica (Dall, 1908).

Description: In der vorliegenden Arbeit wird die Geburt des Kaninchens (multipares S\xc3\xa4ugetier) und des Rindes (unipares S\xc3\xa4ugetier) beschrieben und mit der Geburt anderer S\xc3\xa4uger verglichen. Das Verhalten der Mutter bei der Geburt hat sich nicht ge\xc3\xa4ndert trotz der Domestikation. Die Geburt findet meistens statt zu der Zeit, da die Tiere gew\xc3\xb6hnlich ruhen. Dies wird von Sympathicus-Parasympathicus-Rhythmus bedingt. Die entleerten Uterusteile der Ratte und wahrscheinlich aller Multiparen ziehen sich stark zusammen, weshalb die sp\xc3\xa4teren Jungen keinen l\xc3\xa4ngeren Weg zur Vulva zur\xc3\xbcckzulegen haben und also nicht mehr von Erstickungsgefahr bedroht werden als die ersten.\nDie Lage der uniparen S\xc3\xa4uger kommst zustande infolge Formanbequemung, Gravitation und der Raumverh\xc3\xa4ltnisse in der Bauchh\xc3\xb6hle. Eine ausf\xc3\xbchrlichere Zusammenfassung von Kapitel V findet man auf Seite 23.\nDer erste Atemzug wird ausgel\xc3\xb6st durch die St\xc3\xb6rung des plazentaren Gasstoffwechsels. Nur bei asphyctischen Jungen kann die Atmung einsetzen durch die Wirkung \xc3\xa4usserer Reize (Kap. VI).\nDer spontane Nabelschnurriss der Wale und der Huftiere, ausser dem Schwein und dem Flusspferd, findet statt an einer oder mehreren pr\xc3\xa4formierten Rissstellen. Diese Stellen sind anatomisch und histologisch verschiedenartig gebaut. Bei den Tieren, deren Nabelschnur an einer willk\xc3\xbcrlichen Stelle durchbissen wird oder spontan reisst, sind diese Eigent\xc3\xbcmlichkeiten nicht vorhanden. Eine Zusammenfassung von Kapitel VII findet man auf Seite 46.

Description: During a recent survey of Pacific psammophilous and phycophilous copepods an isolated female Bomolochus was found, the identification of which, in absence of its host, proved to be particularly troublesome. It became necessary to check the descriptions of all species of the genus Bomolochus Von Nordmann, 1832, and of several other genera of Bomolochidae, in the course of which I tried to find a satisfactory grouping of the many species described.\nThis effort in so far proved to be disappointing that a fairly large number of species is so inadequately characterized that recognition, in absence of the host, is next to impossible. Taxonomy of parasitic copepods has, unfortunately, long been influenced by the obstinate notion that each host species should necessarily harbour its own parasitic species. This idea has overstressed the importance of the host, at the cost of information, particularly morphological information, concerning the parasitic animal, so that at present there is an overwhelming number of parasitic copepods of uncertain position, uncertain status or inadequate definition, impeding a much wanted natural grouping of the numerous species of parasitic Copepoda. The importance of complete structural information, especially for those species that are able to leave their host temporarily, cannot be too greatly stressed and it is gratifying to find such information in many of the modern publications (Stock, 1953, 1955; Shen, 1957; Shiino, 1957; Yamaguti, 1936, 1939, 1953, et al.). In the present paper I have presented, in condensed form, all available information on the Bomolochidae; I have suggested a subdivision of the genus Bomolochus, redescribed the female of Bomolochus bellones Burmeister and added the description of two new species. It is hoped that this paper will stimulate the redescription of doubtful or insufficiently described forms, preferably

Description: In the Flora of Tropical Africa C. B. Clarke (6) pointed out that in the collection of \xe2\x80\x9cScleria foliosa Hochst., Abyssinia, prope Chire, Dillon & Petit\xe2\x80\x9d specimens of true S. foliosa Hochst. ex A. Rich. (4) are mixed with some of S. schimperiana Boeck. (1) and that \xe2\x80\x9cit would be very difficult to sort them without looking at the nut\xe2\x80\x9d. He referred S. dillonii Boeck. (2) to the synonymy of S. foliosa, and herein he was followed by all subsequent authors including Nelmes (3) and Robinson (5).\nHowever, already Boeckeler was aware of the fact that the Chire collection is a mixture, and on \xe2\x80\x9cS. foliosa Hb. Dillon et Petit. \xe2\x80\x94 an etiam Richardi? \xe2\x80\x94 pro parte (c. S. foliosa Hochst. intermixta)\xe2\x80\x9d he based his S. dillonii, different from S. foliosa mainly by its globose or depressed-globose, smooth nuts.

Description: This is the second paper dealing with Myxomycetes collected by me in the Netherlands, mostly in the neighbourhood of Doorwerth. Specimens of the species dealt with are preserved either in my private collection or in that of the Botanical Museum and Herbarium of the State University, Utrecht (in the last named case the numbers are followed by a \xe2\x80\x9cU\xe2\x80\x9d), or in both.

Description: In the present study pollen morphology of the Euphorbeaceae is treated as an additional character in taxonomy. Besides the greater part of the genera occurring in the system of PAX and K. HOFFMANN (1931), most of the genera published after 1931 are studied. The pollen grains have been described with the aid of a terminology as simple as possible. In principle the terminology of IVERSEN and TROELS-SMITH has been followed, although in addition, many improvements of ERDTMAN have been used. One of the simplifications is the rejection of POTONI\xc3\x89\xe2\x80\x99s term sculpture. All elements occurring on the endexine are called structure elements; all structure elements together form the structure of a pollen grain. For the sake of consequence endexine apertures and extexine apertures are discussed separately. Different pollen grains are placed in different pollen types. If the differences are of minor importance, the pollen grains are placed in subtypes. Several types can have some characters in common. To express the correspondences, these types are assembled in configurations. As the pollen types in Phyllanthoideae and Crotonoideae differ distinctly, the division of the Euphorbiaceae in these subfamilies is maintained in the discussion of the results. The Phyllanthodieae can be separated in three large groups of pollen types ( Antidesma configuration, Amanoa configuration and Aristogeitonia configuration), which agrees with the grouping of PAX in 1924. The remaining small configurations belong in taxonomic respect to the genera of the Antidesma configuration. In the Crotonoideae many genera possess pollen grains with a croton-pattern. These genera should be treated as a single group. Besides this natural group, the Plukenetiinae possess pollen grains which are clearly distinguished from other genera in the Crotonoideae. Pollen grains of Omphalea are similar to those in the Plukenetia configuration. This pollen-morphological result agrees with the opinion of CROIZAT.\nThe remaining pollen grains in the Crotonoideae are less easy to differentiate in groups. One of the largest configurations is the Mallotus configuration, which includes most genera of the Acalypheae and several genera or other tribes. The Hippomane configuration is another large one. This configuration comprises the tribes Hippomaneae and Euphorbieae. The pollen grains of both tribes are very similar. The genus Pachystroma is pollen-morphologically as well as taxonomically related to the tribe Hippomaneae.\nPera, treated as a separate tribe by PAX and K. HOFFMANN, is related by its pollen grains to some genera in the Acalypheae.\nDalechampia is habitually related to the genera in the Plukenetiinae. Pollenmorphological data, however, do not support this relation. The pollen grains of Dalechampia are not similar to any other pollen type.\nThe morphology of the pollen grains of the Stenolobeae is in agreement with the opinion of PAX, that any separation of these Australian genera is an artificial one.

Description: This work was undertaken at the suggestion of Dr. J. Lanjouw and Dr. F. P. Jonker. The citation heading this paragraph indicates that the group of Caryophyllaceae with which it deals, presents unusual taxonomic difficulties. At first, it was intended to restrict the revision to the genus Gypsophila. However, in the course of the work it was realized that the small genera Bolanthus, Ankyropetalum and Phryna could not be left out of account as they had been regarded by some authors as subdivisions of Gypsophila and by others as near relatives of this genus. For this reason a complete revision of these genera too was included.\nThe only previous revision of Gypsophila is that published by Williams (1889). His study, largely based on data derived from the literature, includes 76 species i.e. about 3/5th of the number recognized here. His views on the generic limits were strongly influenced by those expressed by BENTHAM in BENTHAM and HOOKER\xe2\x80\x99s Genera Plantarum 1 (1862). Later authors did not follow him in this respect, and generally preferred BOISSIER\xe2\x80\x99s delimitation (1867), so e.g. PAX and HOFFMANN in the 2nd Edition of ENGLER und PRANTL, Planzenfam. (1934). PAX had already accepted this delimitation in the first edition (1889).

Description: The new genus Aglaothecium Groenh. is proposed to accomodate the new species A. saxicola Groenh. The development of bitunicate asci as occurring in cryptothecioid genera is compared with that of the supposedly unitunicate but thick-walled asci which are common in Lecideaceae and Lecanoraceae. The question is discussed whether bitunicate asci are always indifferent to iodine.