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Die vorliegende Arbeit soll einen Beitrag zur Biologie der Honigbiene darstellen. Sie ist zunächst eine biologisch-deskriptive Arbeit. Ich habe die Biene bei ihrer mannigfachen Tätigkeit in freier Natur wie auch in ihrem Stocke beobachtet und habe festzustellen versucht, wie sie sich verhält, wenn ihr Körper mit irgendeinem Schmutzstoff in Berührung kommt. ...
Analyse morphologique du splanchnocrane chez les primates et ses rapports avec le prognathisme
(1956)
Chez les Mammifères inférieurs, les mâchoire et les cavités orbtitaires sont situées en avant du neurocrâne; chez les Primates, le massif facial se déplace et est en partie situé sous la cavité cranienne; chez l'Homme, non seulement le massif facial est réduit de volume, mais il est logé entièrement sous le neurocrâne. ...
Un heureux hasard nous a fait acheter, en janvier dernier, pour une experience, une chevre adulte, qui mourut peu de temps apres de dysenterie coccidienne. Le parasite appartenait à l'espece decrite en 1930 par W. L. Yakimoff et Rastegaieva sous le nom de Eimeria Nina-Kohl-Yakimovi. La description originale des auteurs ne comprenait que celle de l'ookyste. Nous avons pu la completer par celle de son cycle evolutif et des Iesions que cette espece determine. Au cours des investigations bibliographiques que nous avons du entreprendre, nous avons ete gene par une certaine confusion dans les travaux concernant les coccidioses du mouton et de la chevre, confusion qui avait ete remarquee par d'autres. Nous avons cru utile, a l'occasion de l'etude particuliere qui se presentait à nous, d'entreprendre un travail plus general et d'essayer de retrouver et de fixer les bases preeises de la zoologie des parasites qui nous occupent. C'est a dessein, pour eliminer des I'abord une cause de confusion, que nous reunissons les coccidies du mouton et de la chevre.
Gli Autori segnalano per il territorio delle Alpi Liguri 144 specie di Molluschi terrestri e 25 specie di Molluschi acquidulcicoli. L'elenco sistematico riporta, per ciascuna specie, eventuali sinonimie, segnalazioni di letteratura e di collezione e i risultati di ricerche di campagna effettuate dagli Autori negli anni 1977-84; inoltre, vengono fornite la geonemia e brevi considerazioni sulla distribuzionc geografica, le caratteristiche ecologichc ed eventuali problemi tassonomici. Segue un esame critico dei taxa di pteseilza dubbia o di incerta collocazione sistematica, ed un breve elenco delle specie presenti nelle aree circostanti l'area in esame, ma assenti in Alpi Liguri. La malacofauna terrestre delle Alpi Liguri (considerate in toto o nei tre Settori del Cuneese, Imperiese e Savonese) viene confrontata con quella di tre settori piu interni delle Alpi Occidentali (Alpi Marittime settentrionali, Alpi Cozie, Alpi Graie), di un settorc alpino meridionale (Alpi Marittime francesi) e di due settori appenninici (Appennino Ligure ed Aipi Apuane), mediante indici di similarit i di tipo binario (presenza-assenza di specie). Vengono inoltre confrontati tra loro gli spettri corologici delle aree sopracitate. L'area studiata non appare uniforme da1 punto di vista faunistico, ma diversamente caratterizzata nei diversi settori. Per la particolare posizione geografica e le peculiari caratteristiche paleoclimatiche, geomorfologiche ed ambientali, il popolamento malacologico delle Alpi Liguri si presenta qualitativamente vario ed ariicchito da correnti rnigratorie di diversa provenienza (alpina, W-mediterranes, appenninicii). Nella caratterizzazione della fauna e degli endemismi, sembra importante il ruolo di area di rifugio assunto dalle Alpi Liguri in epoca glaciale.
Material of the domestic fowl of appropriate ages, ranging from twelve hours' incubation to the adult bird, was prepared for the purpose of studying the production and development of the germ cells. The primordial germ cells arise in the extra-embryonic region anterior to the head fold in the region of the zone of junction during the primitive-streak stage. These germ cells migrate, through the blood stream, to the region of the future gonad, where they develop into the definitive germ plasm. There is no widespread degeneration of the primordial germ cells after their arrival in the gonadal region, nor is there any widespread transformation of somatic cells into definitive germ cells.
Die Untersuchungen wurden während der Jahre 1930-32 in der Newabucht bei Peterhof unternommen. Es wurden 29 Arten der Fische untersucht, wobei als Standartzahl der Sektionen für jede Art 15 Fische genommen. wurden. Für manche seltene Arten konnte man aber nur eine kleinere Anzahl von Exemplaren erbeuten. Im ganzen wurden 368 Fische seziert. Dabei wurde nicht nur die Häufigkeit des Vorkommens (d. h. der Prozentsatz der infizierten Fische) eines jeden Parasiten, sondern auch die absolute Zahl verschiedener Schmarotzer (d. h. die Intensität der Infektion) bei jedem Fisch festgestellt. Im ersten Teil der Arbeit wird die parasitäre Fauna einzelner Fischarten behandelt. Im zweiten Teil werden in systematischer Ordnung Angaben über verschiedene von uns gefundene Parasitengruppen geliefert. Die ganze von uns erforschte parasitäre Fauna enthält 108 Arten, von welcher Zahl 1 auf Mastigophora, 5 auf Infusoria, 24 auf Myxosporidia, 2 auf Microsporidia, 17 auf monogenetische Trematoden, 15 auf digenetische Trematoden, 16 auf Cestodes, 8 auf Aeanthocephali, 9 auf Nematodes, 1 auf Hirudinei, 1 auf Mollusca, 9 auf Crustacea (Copepoda und Branchiura) fallen. Dabei ist ein ziemlich grosser Reichtum an Myxosporidien (24 Arten) und an Cestodes (16) zu notieren, wobei von den letzteren eine wichtige Rolle die Plerocerkoide von DiphylloBothrium batum spielen. Von Trematoden bietet der Fund von Janickia in der Bauchaorte des Hechtes und deren Eier in der Bauchaorte des Hechtes und deren Eier in den Kiemen dieses Fisches, wogegen bis jetzt Janickia nur für manche Cypriniden der Wolga vermerkt war. Die Fauna der Nematoden ist in der Newabucht verhältnismässig arm. Während der Untersuchung wurden nur wenige neue Arten entdeckt, und zwar Ergasilus briani, welcher in einem besonderen Aufsatz (Seite 217) von A. Markewitsch beschrieben wird, und zwei Myxosporidien, deren kurze Diagnose wir hier anführen. Myxobolus luciopercae Petruschewsky wurde zum ersten Mal von Müller in Deutschland entdeckt und von Gurleey in Russland (Don-Fluss) konstatiert, wobei er aber ohne spezifischen Namen beschrieben wurde. Kleine, kugelige, milchweisse Zysten dieser Art sind von 1-2 mm im Diameter und befinden sich hauptsächlich auf dem Kopf des Zanders. Bei starker Infektion sind die Zysten in der ganzen Haut, besonders am Operculum, Kiefern, Auger, und Flossen, verbreitet. Eine derartige Infektion wird von dem Absterben besonders der jungen Zander gefolgt. Die Sporen von M. luciupercae sind etwa 10 mikrometer (9,5-11) lang, 8 mikrometer (7-8,5) breit; die Länge der Polkapseln beträgt 5,2 mikrometer (5-6). Henneguya cutanea Petruschewsky. Diese neue Art wurde von uns zwei Mal in der Haut und an den Flossen von Abramis brama gefunden. Die Zysten dieser Art waren kugelig und erreichten bis 1 mm im Durchmesser. Die Sporen sind in manchen Hinsichteil von den bis jetzt in der Haut und in der Muskulatur der Süsswasserfische gefundenen Henneguya-Arten verschieden ...
As far as we are aware, no previous account of any kind regarding the freshwater and subaerial algal flora of Natal has been published, and the present investigation of one hundred different samples thus affords the first available data on this point. ...
Sesame, Sesamum indicum L. (syn.S. orientale L.) belongs to family Pedaliaceae and is perhaps the oldest oilseed crop known to man. It is an annual, maturing in 70 to 140 days, but usually in 105 days or less, and contains 45-60% oil in its small, flat, oblong seeds which, may be white, brown or black.
Dr. Nonfin (1931) in his book on the "Biology of the Amphibia", while discussing the inter-relationships of Pelobatidae, divides the family into Megophrynae, Pelobatinae and Sooglossinao und points out that among these three "the most primitive genus in the sub-family is the wide spread Megopluys or Megalophrys (including Leptobrachium)". ...
The North Arnerican species of the genus Cremastocheilus are reviewed. These belong to 5 subgenera, Macropodina, Trinodea, Anatinodia, Mymcotonus, and Cremastocheilus. Taxonomie changes are: She inclusion of Crernastocheilus nitens and C. chapini in the subgenus Cremastocheilus rather than Myrmecotonus. Also Anatinodia is elevated to subgeneric status. A key to the subgenera is provided, as is a key to the species of the 5 subgenera, recognizing that the 35 species in the subgenus Cremastocheilus are in need of revision. A critical review of the host records, geographic distribution, and ecology of the Tribe Crernastocheilini (Family Scarabaeidae. subfamily Cetoniinae) is provided. This contains enormous numbers of new records for both the genera Genuchinus and CremastocheiLus both from the literature and from the extensive field work that is reported here for the first time. A Summary of the host records is presented in tabular form. This table shows the association of all species of Cremastocheilus with ants as adults and the larvae either associated with the vegetable material of the ant nests or with vegetable material in rodent burrows. Genuchinus is shown to be a general predator on soft bodied insects while the other genera of the Cremastocheilini are associated with plants, particularly bromeliads. A detailed study of the external morphology and sexual dimorphism of the genera Genuchinus and Crernastocheilus is presented. All species of Cremastocheilus can be sexed with the naked eye by the difference in the shapes of the abdominal terminal Segments, wherein males have the posterior border of the last ventral abdominal segment either straight or slightly bowed, while females have this border broadly rounded. There are other microscopic sexual differences in the structure of the legs. The rest of the external morphology is also presented, particularly from the point of view of adaptations to either a predaceous or rnyrmecophilous existente. Particularly adapted for predation are the pointed maxillae which are used for piercing prey. Particularly adapted for myrmecophily are the mentum, the maxillae, the generally thick exoskeleton, trichomes on both the anterior and posterior angles of the pronotum, the elytra, and the legs (which are adapted to the nest substrate of the host ant nests. Exocrine glands are described for Genuchinus ineptus and at least 1 species of each of the 5 subgenera of Cremastocheilus. In general, there are no gland cells nor glandular areas in Genuchinuc that are comparable to those of Cremastocheilus. The gland cells and glandular areas are quite extensive andvariable arnong species of Cremastocheilus. The frontal gland of some Cremastocheilus (strongly developed in C. castaneus and the C. canaliculatus species group, but weakly developed in the C. wheeleri species group) is described for the first time. Because these glands are not found in Genuchinus ineptuc, a species with general predatory habits, it is thought that these play a role, as yet unknown, in interactions with ants. The life cycles of the subgenera of Cremastocheilus are described. The general life cycle entails adult beetles eclosing in ant nests during the summer and then undertaking dispersal flights. The adults then enter ant nests and ovenivinter there, eating ant larvae during the Winter. Another dispersal flight occurs in the spring during which the adults mate and enter ant nests again. The females then lay eggs and the adults die. The eggs hatch and the larvae spend 3 instars feeding upon vegetable material in the nests. The lmae then pupate in typical scarabaeine earthen cells made of fecal material and soil. These eclose in the summer and the cycle is repeated. Variation from species to species is largely in the timing. Leaving the nest in late Summer, mating seems to be triggered by rainfall in all the species studied. Mating of C. (Macropodina) beameri takes place in rodent burrows. Males seem attracted to females from a distance but the mechanism of this remains obscure. In the subgenus Trinodia, mating takes place on sandy washes or roadsides where females land. In the subgenus Myrmecotonus, maüng also takes place in sandy areas. In C. (Cremastocheilus) mating takes place on sand bars along rivers in the southeastern U.S. and in sand dunes in northeastern U.S. The femaies dig down into the sand. Males locate these places by some unknown mechanism and then dig down to copulate with the females. Field experiments showed unequivocaily that males dig only into areas occupied by females. No sex-specific Sex attractant glands have been located in females so far. Dispersal to ant nests occurs after mating except for C. (Macropodina) beameri which lays its eggs in the rodent burrows and then probably disperses to ant nests. Beetle activity going in and out of nests was studied using wire hardware cloth screens over entrances to Mynnecocystus nests. The mesh size was such that the ants could move freely in or out but the beetles got stuck by their thoraces. The direction then could be interpreted by the direction in which they got stuck. By this method, C. stathamae was shown to leave nests from 23 June to 1 September with a peak on 6 July, just after the beginning of the summer rains. Beetles entered nests from June 23 to August 3, however 39% entered on July 16, probably pulsed by the leaving time which was correlated with the rains. Life cycle timing: C. (Macropodina) develop in the nests of Wood rats (Neotoma sp.]. Females lay about 40 eggs each. The 3 larval instars to pupation take about 1 month. Pupae are found from late August to weil into September. In other subgenera as well, larvae are found in parts of the nest devoid of ants, The timing is similar in all the subgenera found with ants. Mortality factors: While ants attack Cremastocheilus adults, there is no evidence that they are ever killed by ants nor is there evidence that ants kill larvae nor hard earthen pupae cases which protect the pupae. During dispersal fiights and mating, the adults are exposed to predation and evidence is presented that shows predation by horned toads, spiders, magpies, and tiger beetles. Probably most mortality occurs in the larval and pupd stages where the beetles are attacked by internal parasites and fungus. Further rnortality is caused by limitation of the food supply during the larval stage. Reentering nests: Females of C. (Macropodina) beameri select specific rodent and other burrows, attract males for rnating. and then enter the burrow for oviposition. C. stathamae are carried into the ants nests from as far away as 25ft. The beetles appear to land spontaneously after flying randomly over M. depilis nesting areas. Then the wander about waiting for the ants to carry them into the nests. Cremastocheilus hirsutus fly low over the ground searching for Pogonomyrrnex barbatus nests, land. and move straight for the nest entrances which they enter unhindered. Among all species, the ants frequently eject beetles but the net rnovement is in. Ants frequently attacked Cremastocheilus in laboratory observation nests when they were introduced. These attacks seldom resulted in the death of the beetles and the beetles were eventually ignored. When the beetles entered brood chambers, where they fed upon larvae, they were mostly ignored and even licked assiduously by the ants. A principle defensive behavior by the beetles is feigning death (letisimulation). The beetles give off an unpleasant "dead fish odor when collected in the I field. Experiments show that this substance functions to fend off some predators but further experiments indicated that these substances were ineffective against both ants and kangaroo rats. Experiments with various species of Cremastocheilus adults indicate that the adults eat only ant larvae. The beetles will eat larvae of non-host ants but show preferences for the larvae of their normal hosts. Under the same experimental conditions. Genuchinus ineptus adults will feed on a variety of insect adults and larvae. Field experiments on the function of trichome secretions did not indicate that they function to attract ants at a distance nor are they involved in worker acceptance. Laboratory experiments in which areas with a high concentration of gland cells were presented to ants showed that no ants were attracted. Laboratory introduction of Cremastocheilus hamisii adults into Fomica schau.si nests yielded many interactions including ants licking the anterior pronotal angles, the mentum area where the frontal glands empty and a carina over the eye with a dense pad of short setae. These are areas of concentration of gland cells and these are the first observations of licking by ants in specific sites containing exocrine glands. Radioisotope experiments showed food exchange among ants but never from ants to beetles. Other experiments showed that ants can pick up radioactivity from the beetles without feeding on trichome secretions. Evolutionary pathways: Adult Cremastocheilini probably followed the evolutionary route from adult predation on soft bodied insects to specialized feeding upon ant brood and the subsequent development of the beetle larvae in vegetable material in the ant colonies. Thus Genuchininseptus makes a logical outgroup in that they are general predators probably feeding mostly on Diptera larvae associated with Sotol plants in the field. The rnajor evolutionary step taken by Cremastocheiluswas to specialize on ant brood. Then the species radiated into ant colonies inhabiting southwestem North Arnenca. Most of the ant hosts invaded have quantities of vegetable material in their nests sufficient to support several developing scarab larvae. Host colonies are large, contain accessible brood, and are usually dominant foragers Evidence supports the idea that the species of Cremastocheilus have differentes in behavior and morphology that reflect adaptation to the behavioral ecology of different species of ants rather than different evolutionary levels of integration into ant colonies.