265 



as merus and ischium of the external maxillipeds are subequal and the palp is minute and of 

 normal shape. 



As to Parapinnixa Holmes ^) I am completely at loss where to place it, as the literature 

 is inaccessible to me. Alcock brought the genus to the Pinnothei'inae. 



Most of the genera and species of the present group live on the west coast of America 

 and at Japan. 



Key to the genera Pinnotherelia, Pinnixa, Pseiidopinnixa and Tetrias: 



1. Palp of ext. maxillipeds long, narrow, cylindrical, 



segments placed end to end. Carapace not distinctly 



broader than long 2 



Palp of ext. maxillipeds very broad, flattened, surpassing 

 the merus in bulk. Carapace distinctly broader than 



Jong 3 



2. Carapace subrectangular. Last pair of legs not reduced 



in size. Species from Peru and Chile Pinnotherelia H. Milne-Edw. et Lucas 



Carapace subcircular. Last pair of legs reduced in size. 



Species from Japan Pseudopinnixa Ortmann 



3. Carapace generally more than twice as wide as long, 



usually with a transverse crest across cardiac region. 



Propodus of ext. maxillipeds projecting with its 



rounded distal end beyond the insertion of the dactylus. 



Species largely represented along American coasts. Pinnixa White 

 Carapace less than twice as wide as long. Palp of 

 ext. maxillipeds flattened, very much hairy, pro- 

 podus and dactylus widening distally, broadly-tri- 

 angular, merus with a transverse row of hairs . Tetrias Rathbun 



Pinnotherelia H. Mihie-Edwards et Lucas. 

 1843. Pinnotherelia H. Milne-Edwards et Lucas. Voy. Amer. mer. d'Orbigny, v. 6, prt i, p. 24. 



The only known species is P. laevigata (see Rathbun, Proc. U. S. Nat. Mus., v. 38, 

 191 1, p. 546, pi. 51, f. 3), which inhabits the coasts of Peru and Chile. 



Pseudopinnixa Ortmann. 

 1894. Pseudopinnixa Ortmann. Zool. Jahrb., Syst., v. 7, p. 694. 



The genus has been founded on Ps. carinata Ortmann (1. c, p. 694, pi. 23, f. 6), 

 which lives apparently abundantly in Tokyo Bay. 



l) Proc. Califoin. Ac. (2). v. 4, pit 2, 1895, p. 587, founded on ihe West American "■Pinnixa''' ni/ida Lockington. Holmes 

 (I.e., p. 565) first used the term Psetidop'n/tixa, but becoming aware of its being praeoccupied by Ortmann shortly before, he changed 

 it into Parapinnixa. 



"7 



