NO. 1369. NATURAL HISTORY OF THE ISO POD A— RICHARDSON. 



667 



nearly to the middle of the fifth joint of the peduncle of the second 

 pair of antenna\ Second pair of antenna? are about equal to one-third 

 the length of the body; the llagelluni i.s compoised of nineteen or twenty 

 joints. 



The first thoracic segment is but little wider than the head; the mar- 

 gins are entire, with rounded lateral lobes. The sec- 

 ond segment has the lateral margin straight with the 

 epimeron showing slightly along the edge. The third 

 and fourth segments have the antero-lateral lobe 

 rounded, the posterior margin straight, with the 

 epimeron showing as a rounded lobe. The fifth, 

 sixth, and seventh segments have rounded lateral mar- 

 gins with epimera showing on the posterior part or 

 the segments. 



The terminal segment is rounded posteriorly witii 

 smooth margins and a median lobe between the uropoda. 

 Uropoda \evy short, about half as long as the ter- 

 minal segment. Branches about equal in length, and 

 twice as long as the peduncle. 



Legs simple, ambulator}', similar in shape and size, 

 and l)iunguiculate. 



Onh' two good specimens, both females, were taken at Sausalito, 

 California, by Dr. Ritter and party. Two imperfect specimens also 

 are from the same locality. 



Until now the only other known species of this genus was Janiropsis 

 hretHi'et/tisSav^."^ As that author has pointed out. this 

 genus diflers from Jaiiira^ to which it is very closely 

 related, in the much shorter uropoda; in the shorter 

 second pair of antenna?; in the structure of the first 

 pair of antenna?, which have the tiagellum composed of 

 onl}' a restricted number of articulations; in the struct- 

 ure of the first pair of legs in the male, these being 

 "remarkably developed, prehensile, much longer than 

 any of the other pairs, with the carpal joint f usiforndy 

 dilated" — in the female, however, this pair do not 

 differ from the other legs, all being ambulatory in i-har- 

 acter; in the greatly dilated joints of the maxillipeds, 

 and in having the tip of the middle piece of the male operculum pro- 

 duced and dilated at the distal extremitv. 



Fig. 13.— Antekiob 

 part ok body of 

 Janiropsis cali- 

 fobnica. x 27. 



Fig. 14.— Posterior 

 PART OF body of 

 Janiropsis cali- 

 fornica. x 27. 



JANIRA OCCIDENTALIS Walker. 



Janira occidentalis W.\lkek, Trans. Liverpool Biolopk-al Soc, XII, ISitS. pp. 280- 

 281, pi. xv, figs. 7-10.— RicnAKDsox, Proc. U. S. Nat. Mus., XXI, 1899, 

 p. 859. 



Locality. — Puget Sound. (Harriman Alaska exi)e(litioii.) 



« Crustacea of Norway, II, 1899, p. 98. 



