TANAIDACEA AND ISOPODA— TATTERSALL. 231 



alternating with one another, and for the species S. neaera, S. convexa, S. miiiuia, and 

 S. pallida he figures such an arrangement. Hodgson, in descriVjing S. trilohitoides, 

 Eights, gives as one of the specific characters " special spines on the propodus of 

 the second thoracic appendage consisting of sensory teeth alternating with broad 

 leaf-like sensory structures, of which the blade is unequally developed on the two sides 

 of the shaft." Hodgson gives figures of each of these spines, showing each to possess a 

 mid-rib terminating in a peculiar sensory structure. CoUinge, on the other hand, 

 speaking of S. septemcarinata, states that he was unable to find more than one kind of 

 spine, which he describes as terminating in three or four finger-like processes. My 

 own observations agree with those of Beddard and Hodgson. I have examined the 

 five species in this collection from this point of view, and in all five I have found the 

 propodus of the second thoracic limb to be armed with two kinds of sensory spines 

 regularly alternating with one another and having essentially the general structure 

 indicated by Hodgson. The shape of the spines varies somewhat in each species, 

 particularly those which Hodgson calls "leaf-like organs," which are sometimes leaf- 

 shaped and sometimes longer and narrower as figured by Beddard for some of his 

 species. I found both kinds present in S. septemcarijiata (pi. VH, fig. 3), though 

 CoUinge was only able to find one kind, the rod-like, more obviously spine-like type. 



S. glacialis is here recorded from a locality which is further South than that at 

 which any species of the genus has been taken before. It is thus a true Antarctic 

 species. 



37. Serolis pagenstecheri, Pfeffer. 



S. pagenstecheri, Pfeffer, 1887, p. 73, pi. II, figs. 1, 2, pi. IV, figs. 1-3. 



Occurrence. — Leith Harbour and Cumberland Bay, South Georgia, December, 1913, 

 collected by P. Stammwitz, two females. 



Remarks. — The specimens respectively measure 45 mm. long by 37 mm. broad, 

 and 37 mm. long by 83 mm. broad. I have nothing to add to Pfeff"er's description 

 and figures of this species, which are sufiicient for its ready identification. The 

 species belongs to that group of the genus having the coxae of the first three free 

 thoracic segments separated by a distinct suture from their terga. The species has 

 not been recorded since Pfeffer described it, and the present specimens are from the 

 type locality. 



38. Serolis p>olita, Pfeff"er. PL VII, fig. 6. 



S.polita, Pfeffer, 1887, p. 81, pi. II, figs. 3, 4, pi. IV, fig. 4 ; Richardson, 1906 (2), p. 7 ; 

 Richardson, 1911, p. 396. 



Occurrence. — King Edward Cove and Cumberland Bay, South Georgia, November 

 and December, 1913, collected by P. Stammwitz, five males and one female. 



Remarks. — The male specimens measure 15-17 mm. in length by 14-16 mm. in 

 breadth; and the female, 12mm. by 10 -5 mm. The first three free thoracic somites 



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