The Cumacea of the Puritan Expedition. 417 



of the pseudorostrnm , the teeth on the anterior margin, above the 

 anteunal uotch, are longer thau in the tvpe-specimen, and those on 

 the lower edge of the pseudorostrum are apparently not always 

 present. The most important difference, however, is in the pro- 

 portions of the antennule. In the younger specimens this 

 appendage agrees fairly well with the figure and description already 

 given. In those approaching maturity, however, and in the adult 

 female (fig. 9) it is mueh more slender, with the last segment of 

 the peduncle longer by ahout Vg than the preceding and a little 

 longer thau the external flagellum. The brauchial siphon is in some 

 cases protruded to a greater length than in the type-specimen, 

 sometimes to considerably more thau the length of the carapace. 

 At the tip of the endopod of the uropods what was described as 

 a "long slender spine" is in reality a stout, piumose seta and, in 

 addition to the spine at the base of this seta, the distai segment 

 of the endopod has three spines on its inner edge. 



The adult male specimens are unfortuuately fragmentary. No 

 teeth appear on the dorsal edge of the carapace nor on the lower 

 edge of the pseudorostrum. Save for the absence of the anteunal 

 notch, the armature of the antero-lateral margin of the carapace 

 seems not to differ greatly from that of the female. 



In referriug to L. temdrostris^ Sars, as the only species 

 agreeing with the present one in having a large inner ramus on 

 the antennule, I overlooked Zimmer's L. septemdentatus (Hamburger 

 Magalhaensische Sammelreise, Cumacea 1902 p. 3) which however 

 is distinguished by the widely open anteunal notch and other 

 characters. As has been shown above L. longirostris Sars must 

 now he added to the same group of species. 



Occurrence. — Stations 8, 17, 18, 26, 29, 44. Depth 100— 

 1100 metres. 



Family Naniiastacidae. 



Cum ella sp. 



Two female specimens which, though nearly or fully adult 

 measure only about 1,75 mm. in total length, occurred at Station 29. 

 They appear to difler in certain characters from ali the described 

 species of the genus, but as neither of them is in a very good 

 state of preservation I bave not thought it advisable to attempt to 

 diagnose the species. 



