19 



squama is always smooth. The marginal rim of the carapace leaves a laminar expansion at the 

 lower part of the posterior margin ; this expansion is narrow in the smaller specimens, broader 

 and well developed in two adult females. Some of the features enumerated show that the 

 "Siboga" specimens are intermediate between the specimen described and figured by Sars and 

 that examined by Ortmann. 



The largest specimen, a female with marsupium fully developed, measures 52.4 mm.; the 

 smallest specimen is 41.5 mm. — It may be added that the two stations 141 and 143 show that 

 the specimens were taken in intermediate layers and at least about 450 m. from the bottom. 



II. Family EucopinxE G. O. Sars. 

 Eucopia Dana. 



In Buil. Mus. Oc. Monaco N n 42, 1905, I stated that G. O. Sars in his Challenger Report 

 "has mixed together at least three species of Eucopia', that E. australis Dana is a very large 

 antarctic species which differs not only from E. sculpticauda Faxon but from E. unguiculata 

 Will.-Suhm, finally that the "Siboga" material contains a large female, which I was unable to 

 refer to any previously known species. Ortmann (1906) adopted my view that E. australis Dana 

 ought to be separated from E. unguiculata W.-S., but the localities for the specimens referred 

 by him to E. australis suggest that they do not belong to Dana's antarctic species but to E. 

 major n. sp. secured by the "Siboga" and described below, and the fact that I have specimens 

 captured by Prof. A. Agassiz in the Pacific supports that suggestion. During a stay in London 

 1907 I examined the "Challenger" Schizopoda preserved in the British Museum (Natural History), 

 and I found 4 specimens referred by Sars to E. australis Dana. Among these a specimen from 

 Stat. 107 and marked "male" and "type" on the label belongs to E. sculpticauda Faxon; a 

 specimen from Stat. 50 (in North Atlantic) belongs to E. unguiculata Will.-Suhm, and two 

 specimens from Stat. 158 (lat. 5o°i'S., long. i23°4'E.) belong to E. australis Dana, and one 

 of these is about half-grown, while the other is an adult female measuring about 50 mm. in 

 length. — Finally I established (Buil. Mus. Oc. Monaco, N° 30, 1905) E. intermedia on a single 

 specimen, but a subsequent study of much more material gave the result that the characters 

 pointed out — though very striking — are due to age, the specimen being a very young E. 

 sculpticauda Faxon with the anterior thoracic legs considerably more slender than in the adults 

 and with a telson differing from that of the adult in possessing no "network of ridges enclosing 

 honeycomb-like cells" on its surface and showing no lateral constriction a little in front of the 

 tip. Consequently -E. intermedia H. J. H. must be cancelled and referred as a synonym to 

 E. sculpticauda Fax. 



Thus the genus Eucopia comprises at present 4 species. The following key gives the 

 distinguishing characters of the adults and of specimens somewhat more than half-grown; in 

 half-grown or still smaller specimens some of the characters (length of eye-stalks, adornment on 

 the surface of telson, relative length of the distal joint of the exopod of the uropods) are less 



