,-MT7>A» I 



Zoologischer Anzeiger 



herausgegeben 



von Prof. J. Victor CarUS in Leipzig. 



Zugleich 



Organ der Deutschen Zoologischen Gesellschaft. 



Verlag von Wilhelm Engelmann in Leipzig. 



XXL Band. 2. Juni 1898. No. 560. 



Inhalt: I. Wissenschaft!. Mittheilnngen. 1. Lönubergr, Some biological and anatomical 

 facts concerning Parastacus. (Schlut's.) 2. v. konmickî, Flügelrudimente bei den C'araben. 3. t. fcoiii- 

 liicki, Erythropodismus der Laufkäferarten. 4. Schulze, Nonienclaturfragen. 3. Die Erhaltung der 

 Species- und Gattungsnamen. 5. Nassouow, Sur les organes phagocytaires chez le Strongylus 

 rmatus. 6. Michaelsen, Vorlâutige Mittheilung über einige Tunicaten aus dem Magalhaensischen 

 Gebiet, sowie von Süd-Georgien. 7. Tomier, Ein fall von Polimelie beim Frosch mit Nachweis der 

 Entstehungsursacben. II, Slittheil. aus Museen, Instituten etc. Zoological Society of London. 

 Personal-Notizen. Necrolog. Berichtigung. Litteratur. p. 209—224. 



I. Wissenschaftliche Mittheilungen. 



1. Some biological and anatomical facts concerning Parastacus. 



By Dr. Emar Lön nberg, Upsala Sweden. 



(Schluß.) 



The antenne of the females are also, contrary to what could be 

 supposed, comparatively a trifle longer than those of the males, at 

 least this is the case with the specimens I have examined. In those the 

 tips of the antenne reach, when laid back, to the posterior margin of 

 the second abdominal somite, but in the males only to the first. 



One of the males being an exception, it is possible that a com- 

 parison of a greater number of specimens will give a different result. 



The females also seem as a rule, to be smaller to judge from my 

 specimens. 



When the sexual dimorphism is so plainly developed it was not to 

 be expected that these Parastaci after a closer examination of the genital 

 organs would turn out as hermaphrodites. After removing the carapace 

 I found in the female specimens a large ovary with well developed reddish 

 looking eggs, and in the males a testis of normal size and colour. Both 

 testis and ovary extend anteriorly to the stomach, posteriorly the ovary 

 ends in the last thoracic somite , but the testis in the one next to 

 the last. Both genital glands may be said to be composed of two por- 

 tions of nearly the same size and placed in a straight angle to each 



2.5 



