Mr. A. O. Walker — Notes on Amphipoda. 33 



For references see ' Das Tierrelcli,' Amphipoda Gam. 

 pp. 655 & 739, under Jassa ocius j also Chevreux, Result. 

 Camp. Monaco, p. 107. 



H. ocius is well described in the e Tierreich' Gammaridea 

 and well figured by Delia Valle, whose figure of gnatho- 

 pod 2 ^ is erroneously marked " ? ," but correctly referred 

 to in the text. To the characters given by various authors 

 may be added the following : — 



Antenna 1 : the accessory flagellum is so thin that when 

 closely applied to the joint, as it usually is, it can only be 

 distinguished by the fringe of unequal setee on its truncate 

 extremity. 



Gnathopod 2 : the palm is so densely clothed with plumose 

 setse that it is difficult to see it3 structure. 



Podocerus (Jassa?) dentex, Czerniavski, is referred to 

 H. ocius by Delia Valle and Chevreux, while Stebbing 



(Tierreich Gamrn.) gives it as a distinct species and identifies 

 it with Podocerus herdmani, Walker ( = P odontonyx, G. O. 

 Sars). As Czerniavski does not describe the uropods, it is 

 impossible to be certain on this question, but he says that 

 the accessory flagellum of antenna 1 is " rudimentary" — a 

 character that suits H. ocius better than J. herdmani. His 

 description of the hand of gnathopod 2 with " dentibus duobus 

 posterioribus magnis " (two large posterior teeth) agrees 

 perfectly with H. ocius, while a reference to Sars's figure of 

 Podocerus odontonyx ( = Jassa herdmani) in Crust. Norway, 

 pi. ccxiii. fig. 2, will show that this species has only one 

 posterior tooth, which I have never known to be bifid. As 

 to the question of the distinctness of J. herdmani from J.fal- 

 cata (Montagu), = J. pulchella, Leach, see Anu. & Mag. Nat. 

 Hist. ser. 6, vol. xv. p. 473, and Trans. Liverpool Biol. Soc. 

 \ ix. p. 314; also Norman & Scott, Crust. Devon and 



. jrnwall, p. 92. 



) The Genus Leptocheirus. 



This has hitherto been classed with the Photida?. I venture 

 to suggest that its proper position is in the Aoridse, with 

 which it is connected by such forms as Goremapus versicu- 

 latus (Bate) and Lembos leptocheirus, A. O. W. (Trans. Linn. 

 Soc, 2nd ser. Zool. vol. xii. (1909) p. 338, pi. xliii. fig. 7). 

 The first gnathopods, though not (except in L. cornu-aurei, 

 Sovinski) longer, are certainly stronger than the second. 



Ann. & Mag. N. Hist. Ser, 8. Vol. vi. 3 



