l68 CRUSTACEA MALACOSTRACA III. 



they had seen a very large number of specimens, but excepting jE. venfrosa, not one female 

 with marsupium, and consequently they maintained that females with marsupium of these forms must 

 be found on the bottom of the sea. The "Ingolf" has proved the correctness of this view, as it has 

 taken with trawl or dredge two females with marsupium of <&ga psora L,. in depths of about 300 fath., 

 and five similar specimens of sga arctica Liitk. at three stations with depths from 568 to 799 fath. 

 These facts are pointed out here because they are of special interest 



As to morphology a few points may be briefly mentioned. As already said, the antennae have 

 only five joints in the peduncle; it was even impossible to find any vestige of a praecoxa. -- In the 

 above-named paper on Cirolanidae etc. (1890) a detailed description with figures of the mouth-parts in 

 both sexes of two genera of the ^ginse is found; I showed the extreme expansions of the proximal 

 parts of the maxillipeds in ovigerous females of Rocinela, and stated that in ^Zga a similar structure 

 was found. I refer to these facts, as authors -- f. inst G. O. Sars in his standard work generally 

 examined the mouth-parts of females without marsupium or of males, overlooking the extreme differ- 

 ences between the maxillipeds in such specimens and in females with marsupium. 



The material comprises representatives for three genera. 



Leach. 



Of this rich genus eight species have been collected within our area. No new species was 

 found, and seven of the forms have been described and figured not only by Schiodte & Meiuert (op. 

 ciL) but by G. O. Sars, so that they are very well known. 



in. jEga psora L. 



1761. Oniscus Psora Linne, Fauna Suec. Ed. II. p. 499. 



! 1879. jEga Psora Schiodte & Meinert, op. cit. p. 357; PI. VIII, figs. 5-6. 

 ! 1897. psora G. O. Sars, Account, II, p. 59; PL 24. 



1905. Richardson, Monograph, p. 168, fig. 148. 



Two females with marsupium have been taken by the "Ingolf", and the largest specimen is 

 36-2 mm. long and 18-5 mm. broad. Schiodte & Meinert stated their largest female without marsupium 

 to be 48 mm., and the largest specimen measured by me is 49-5 mm., but in this and other species of 

 j&ga the animals taken on fishes are frequently much distended, due to an enormous quantity of food, 

 and consequently the thoracic segments are removed from each other. 



Schiedte & Meinert recorded ^E. psora as taken on Gadus morrhua and Somniosus microcepha- 

 lus. Our Museum possesses specimens taken on the same fishes and, besides, on Gadus ogac, Hippo- 

 glossus pinguis, Hippoglossns vnlgaris and A narrhichas latifrons. Sars has, besides, recorded it from Gad-its 

 teglefinns and Molva vulgaris, Richardson from Cottus scorpius and Raja batis. 



Occurrence. Taken by the "Ingolf at two stations. 



