A molecular method for the detection of sally lightfoot crab larvae (Grapsus grapsus, Brachyura, Grapsidae) in plankton samples

The decapod Grapsus grapsus is commonly found on oceanic islands of the Pacific and Atlantic coasts of the Americas. In this study, a simple, quick and reliable method for detecting its larvae in plankton samples is described, which makes it ideal for large-scale studies of larval dispersal patterns in the species.     

Beobachtungen und Fragen zur Biologie des Kolkraben (Corvus c. corax L.)

Ohne Zusammenfassung     

Beobachtungen und Experimente zur Biologie des Regenwurms. I. (Lauterzeugung. Formsinn und chemischer Sinn.)

Ohne Zusammenfassung     

Distribution of decapod larvae in the surface layer of an isolated equatorial oceanic archipelago: the cases of benthic Grapsus grapsus (Brachyura: Grapsidae) and pelagic Sergestes edwardsi (Dendrobranchiata: Sergestidae)

Two different decapod larval assemblages inhabit the marine environment of Saint Paul’s Rocks, differentiating the inlet from the surrounding oceanic waters. Larvae of the crab Grapsus grapsus and of the holopelagic shrimp Sergestes edwardsi are abundant in superficial waters of the archipelago and have previously been shown to be good indicators of the inlet and adjacent oceanic waters, respectively. We investigated the horizontal, diel and temporal distribution of these species at Saint Paul’s Rocks. Horizontal surface hauls were conducted from 2003 to 2005, in the inlet and at four increasing distances from the archipelago, in the morning and at night, using a 200-μm mesh net. Larvae of G. grapsus were identified in samples from all expeditions and abundance was found significantly higher at night in the inlet site. Only larvae in the first zoeal stage were found in samples, highlighting the importance of the area for this species reproduction. On the contrary, the distribution of larvae of S. edwardsi was typical of a holopelagic species, which are permanent residents of the water column and spawn in oceanic areas, indicating that the islands are of little influence to them.     

Beobachtungen zum Paarungs- und Aufzuchtverhalten der Wasserspitzmaus Neomys fodiens (Soricidae)

Five European Water Shrews (Neomys fodiens) were kept in an indoor enclosure of 2.7 m² where one couple mated regularly. Multiple copulations appeared over a period of about 12 hours. Ten litters with 56 offspring were born and 33 survived. The female gave birth to her latest litter at an age of about 20 month, 2 month later as the end of the reported lifespan in nature. The period of fertility lasted 336 days and is comparable to those of Crocidura. At the end of this period three times signs of pseudopregnancy were detected: After copulating the female started building her nest and intensified this behaviour after about three weeks, at the end of the expected “gestation” swollen nipples could also be noticed, but no offspring inside the nest. The female died at an age of about 38 month.After successful copulations a copulatory lock was achieved and the female could track her mate. The mating behaviour can be classified as follows: a) male entering female's territory, b) precopulatory chasing, c) approaching of the mates, d) mounting and repeated copulations attempts, e) successful copulation, male slipping down from female's back, f) copulatory lock and resting, g) cleaning sexual organs, h) continuing chasing and further copulations or i) displacing the male and finishing sexual behaviour. Driving off the male from female's territory could last some time. No special calls were uttered in the close context of copulatory behaviour, only the known ones while chasing, some low contact calls inside the nest and aggressive calls while driving off the male.     

Untersuchungen zur Biologie der endotrophen Mycorrhiza bei Zea mays L. und Avena sativa L.

Ohne ZusammenfassungGekürzte Fassung einer Dissertation an der Mathematisch-Naturwissenschaftlichen Fakultät der Universität zu Köln.     

Beobachtungen am Nest der Zwergrohrdommel) (Ixobrychus m. minutus L.)

Ohne ZusammenfassungVortrag, gehalten auf der Jahresversammlung der D.O.G. in Berlin, Okt. 1934     

Untersuchungen zur Anatomie und zum Erbverhalten der Samenschalen vonCucurbita maxima Duch. undCucurbita pepo L.

Ohne ZusammenfassungMit 11 Textabbildungen     

Beitrag zur Biologie der Schellente(Bucephala clangula)

Ohne Zusammenfassung     

Beitrag zur Biologie und zur Kenntnis der Verbreitung des Madagaskar-M?hnenibisses,Lophotibis cristata (Boddaert)

Zusammenfassung Es wurden die Verbreitung des Mähnenibisses,Lophotibis cristata, in der Mangoky-Region und dessen Anwesenheit während des Jahres dargestellt sowie einige Beobachtungen über die Biologie wiedergegeben und zum ersten Mal Nest, Eier und Junge näher beschrieben. Jedes der zwei beobachteten Nester befand sich auf einem Kily-Baum,Tamarindus indica. Beide Gelege zählten je 3 Eier.     

Untersuchungen zur Biologie des Wasserschmetterlings Nymphula nymphaeata L. (Lepidoptera,Pyralidae)

Investigations into the Biology of the Water Moth Nymphula nymphaeata L. (Lepidoptera, Pyralidae)