AMPHIPODA FROM BAY OF BISCAY. 223 



rostrum to tip of uropods, while the largest males were only 18-19 mm. 

 There were only a very few small ones, and of these the smallest was 

 9 mm, long. The two specimens from Station X agree in all structural 

 details with these large ones, the only difference being the degree of 

 development of the dorsal processes on the two last peraeon-segments 

 and the two first pleon-segments, which in the larger specimens are 

 greatly produced. The variation in size is not confined to this species. 

 Stebbing has noted a similar case in Parathcmisto ohlivia (40), p. 37 ; 

 and it was one of Norman's principal reasons for separating E. gracilipes 

 from JE. comirressa (27), p. 51. 



The pouches of all the females (May, 1909) were greatly distended 

 with either young just hatched or with eggs nearly hatched. Owing 

 to the extrusion of most of the contents of the pouches it was im- 

 possible to estimate the number carried by any one female. It must, 

 however, be considerable ; one female, 20 mm. long, had 71 young, 

 each measuring 1"5 mm., still remaining in the pouch. In view of 

 Sars's remarks as to the peculiar armature of the 6th joint of the 3rd 

 peraeopod forming a constant specific character in the very young 

 specimen equally with the adult, it may be worth while to note here 

 that in the larval E. hispinosa all five peraeopods are practically sub- 

 equal in length, and the 3rd is not distinguishable from the others. 

 The proportions of the joints are quite different also, e.g. the finger 

 of the 3rd peraeopod is nearly as long as the preceding joint. 



Fam. LYCAEIDAE. 



Gen. Brachyscelus, Bate. 



Brachyscelus crusculum, Sp. Bate. 



Station X. One specimen, an ovigerous female, 8-5 mm. long. 

 ,, XI I. One specimen, a large ovigerous female, 17*5 mm. 



For the discussion as to the identity of Thamyris mediterranea 

 Glaus with Bracliyscelus crusculum Sp. Bate, see Norman (26), p. 134 ; 

 Tattersall (43), p. 26 ; and Stebbing (40), p. 41. I have not seen any 

 males of this species, but an examination of the two female specimens 

 mentioned above would seem to support Norman's view that T. medi- 

 terranea is only a young stage of B. criisculum. In the small female 

 the 3rd uropods reach to nearly the level of the telson, as in Senna's 

 figure 10 (33), p. 8, while in the large female the telson extends con- 

 siderably beyond them, as in Chevreux's figure 8 (11), p. 74. 



