168 



BULLETIN 97^ UNITED STATES NATIONAL MUSEUM. 



PINNIXA AFFINIS Rathbun. 



Pinnixa affinis Rathbun, Proc. U. S. Nat. Mus., vol. 21, 1898, p. 606, pL 

 43, figs. 7-9 (type-locality, Panama Bay, 26 fathoms; female holotype, 

 Cat. No. 21594, U.S.N.M.). 



Diagnosis. — Lower margin of palm of female mostly convex; 

 pollex short; posterior margin of merus of third ambulatory leg 

 armed with spinules or small spines. 



Descnption. — Allied to P. occidentalis. Carapace of female 

 broader than in occidentalis, regions distinctly indicated, cardiac re- 



FiG. 105. — Pinnixa affinis, female holottpe. a, Dorsal view, X 3 ; 6, endognath 



OF OUTER MAXILLIPED, X 22%. 



gion crossed by a blunt, transverse, bilobed crest; surface punctate, 

 punctae largest on branchial regions. Antero-lateral border of bran- 

 chial region a granulate line. Front not advanced beyond line of 

 subhepatic region. Third joint of palp of outer maxilliped articu- 

 lated near proximal end of inner side of second. 



Chelipeds smooth, pubescent ; lower margin of palm convex except 

 near base of pollex, which is short, very broad, deflexed, prehensile 



edge irregularly dentate, terminating in a 

 short, acute spine; dactylus with a large 

 tooth at basal third; fingers not gaping 

 when closed. 



First two legs slender, margins of pro- 

 podal joints subparallel; first reaches to end 

 of propodus of second; second to end of 

 propodus of third. Third leg broadest; 

 merus very hairy along margins; posterior 

 margin armed with spinules, those near middle larger and spine- 

 like; anterior margin granulous. Fourth leg reaches about to end 

 of carpus of third ; propodus narrow, as in first and second. 



Measurements. — Female holotype, length of carapace 3.4, width 

 of same 7.3 mm, 



tSfcdmen examined. — Panama Bay, lat. 8° 27' 00" N. ; long. 79° 

 35' 00" W.; 26 fathoms; gn. M.; Mar. 30, 1888; station 2803, Alba- 

 tross; 1 female with eggs, holotype. Cat. No. 21594, U.S.N.M. 



Fig. 106. — Pinnixa affinis, 

 right chela of female 

 holotype, x 13. 



