TANAIDACEA AND ISOPODA— TATTERSALL. 203 



examination revealed a few small but constant differences. The body is more compac 

 than in H. antarctica, and rather broader proportionally than in the latter. It is 

 covered by a not very close pile of short hairs, whereas the body of //. antarctica is 

 practically smooth. The pigment, as I have already remarked, is not so intensely 

 developed or so well marked as in H. antarctica, but is much more subdued and diffuse, 

 as Vanhoffen shows. The coxal plates of the first four free thoracic somites are 

 rounded, those of the last three somites bluntly pointed. In this character they are 

 sharply distinct from H. antarctica, in which all the coxae are acute. The antennae 

 are long, and have a flagellum composed of fifty-six to sixty joints. The second 

 thoracic limb of the female (pi. I, fig. 11) closely resembles that of //. antarctica, but 

 that of the male (pi. I, fig. 14) is quite distinct, and there is not nearly so strikino- a 

 sexual dimorphism as I have described for H. antarctica, unless, indeed, I have only 

 seen immature males. Compared with the same limb in immature males of 

 H. antarctica the second thoracic limb of M. maculata has the carpus shorter and 

 broader, and the palmar edge evenly curved without any trace of the palmar tooth of 

 the former species. The uropods (pi. I, fig. 12) are quite distinct, those of 

 H. antarctica being short straight one-jointed appendages, whereas in M. maculata 

 these appendages are strongly curved and hook-like with two or three subsidiary 

 spinules. The median lamellae of the operculum of the males of Iwth species are closely 

 similar, as my drawings show (pi. I, fig. 13, pi. II, fig. 3). Finally, on the lateral 

 margin of the abdomen of H. antarctica, about half-way down, there is a short 

 transverse row of stout sensory hairs, forming quite a conspicuous lateral tuft. These 

 hairs are absent in M. maculata. 



From M. maculata as described by Vanhoffen, my specimens differ in the absence 

 of dorso-lateral spinules on the abdomen, and in some minor details in the form of the 

 second thoracic limb of the female. Vanhoffen says nothing about the uropods of his 

 specimens. 



Genus HALIACRIS, Pfeffer. 

 10. Haliacris antarctica, Pfeffer. PI. I, figs. 15, 16 ; PI. II, figs. 1-3. 



S. antarctica, Pfeffer, 1887, p. 137. 

 (?) H. australis, Hodgson, 190:^, p. 253, pi. XXXIV, fig. 1, and pi. XXXVII ; Richardson, 1906, 



p. 16; 1908, p. 5. 

 (?) H. antarctica, Hodgson, 1910, p. 58 ; Richardson, 1913, p. 19. 



Munna antarctica, Vanhoffen, 1914, p. 562, text-fig. 90a and h. 



Occurrence. — Cumberland Bay and King Edward Cove, S. Georgia, December, 

 1913, collected by P. Stammwitz, one adult male, three sub-adult males, two adult 

 females, and three juvenile specimens, 2-4 mm. 



Station 220, off Cape Adare, mouth of Robertson's Bay, 45-50 fathoms, bottom 

 fauna, two immature males, 2-5 mm. 



Remarks.— A. have no doubt whatever that the specimens from S. Georgia, which is 

 the type locality, are referable to Pfeffer's species. Their examination has yielded very 



