On new Species of Antarclic Ampliipoda, 13 



HI. — rrdiminary Descriptions of neio Species of Amphipoda 

 from tlie 'Discovery'' Antarclic Expedition, 1002-1901. 

 "By Alfred 0. VValkek, F.L.S., F.Z.S. 



[Continued from vol. xvii. p. 458.] 



Proholoides antarcticus^ .sp. ii. 



W.Q. from Feb. to Dec. 1902 : in sponges i^c. 



General chnracter.s as in PrchoJoides [ProboHuni) gregarium 

 (Sars). 



First gnathopods. — Female : wrist subequal in length to, 

 but wider than, the hand, the hind margins of both convex 

 and setose. ]\]ale: wrist considerably longer and but slightly 

 wider than the hand ; otherwise like the female. 



Second gnathopods. — Female : carpal process rounded, 

 setose; hand with subparallel margins; hind margin sub- 

 equal to the [»alm, which is defined by a small tooth and two 

 spines. Male: hinder part of the loxoer margin of the side- 

 plates irregularli/ serrate. Hand as long as the three preceding 

 joints, the hind margin shorter than the front and terminating 

 in a sharp toothy forming the palmar angle ; pahn deeply exca- 

 vate, uith a central tooth and a denticulate ridge near the 

 hase of the daciylus. In a younger male the palm is less 

 deeply excavate, the central tooth wider, blunter, and denticu- 

 late, and the ridge as wide as the excavation. 



Third perceopods : the concave hind margin of the narrow 

 first joint is produced almost to the end of the second, ter- 

 viinating in a divided lobe. 



Fourth and fifth perceopods as in P. gregarium (Sars) . 



Third uropods ; peduncle shorter than the ramus, with 5 

 spines ; first joint of ramus subequal to second, with 3 spines. 



Telson reachins: the end of the oeduncle of the third 

 uropods, with 3 spines on each margin. 



Length of female 3"5 mm. ; the male considerably larger. 



Proboliella, gen. nov. 



Mandibles with a two-jointed palp. 



First maxillae with a two-jointed palp. 



Maxillipeds with the inner plates divided to the hase, the 

 outer more or less developed. 



Second perseopods riot stronger than the first. 



Third perteopods with the first joint narrow ; fourth and 

 fifth pair with the first joint expanded. 



