246 BULLETIN 152, UNITED STATES NATIONAL MUSEUM 



Caracas Bay, Curasao; 1920; C. J, van der Horst: In coral; April 

 7; 1 male, 1 female (56884), 2 males, 1 female (Amsterdam Mus.); 1 

 male and 1 female have both branchial regions swollen by isopod 

 parasites. May 1 ; 1 male, parasitized on both sides (Amsterdam 

 Mus.). 



Cartagena, Colombia; College of San Pedro Apostal; 1 female 

 (53410). 



Bermudas; J. Matthew Jones; received from A. E. VerrHl; 1 male 



(24862). 



Genus PLATYPODIA Bell 



Platypodia Bell, Trans. Zool. Soc. London, vol. 1, 1835, p. 336; type, P. granulosa 

 (Rtippell) = Xardho granulosus Riippell, 1830, = Cancer limhatus Milne 

 Edwards, 1834. — Rathbun, Proc. Biol. Soc. Washington, vol. 11, 1897, p. 158. 



Lophadaea A. Milne Edwards, Ann. Sci. Nat., ser. 4, vol. 18, 1862, p. 43; type, 

 L. granulosa (Riippell) = Xantho granulosus Riippell. 



Carapace moderately broad, convex in both directions; regions 

 generally well delimited and subdivided into lobes; surface generally 

 (not always) granular; antero-lateral borders with an independent 

 crest-like edge, generally thin and sharp and distant!}^ fissured; 

 postero-lateral borders rather concave. Front a little deflexed, about 

 a fourth the greatest breadth of carapace, grooved and emarginate in 

 middle line. Orbits large, three suture lines near outer angle distinct. 

 Eyes on short thick stalks. Antennules folding obliquely trans- 

 versely; inter-antennular septum broad. Basal article of antennae 

 short, touching front only; flagellum lodged in orbital hiatus. Merus 

 of external maxillipeds with front edge a little oblique. Chelipeds 

 equal in both sexes; fingers pointed, not hollowed at tip. Long 

 joints of legs with sharp crest-like upper borders. Abdomen of male 

 five-jointed, tliird to fifth somites being fused. 



Inhabits the Indo-Pacific region besides both coasts of middle 

 America and the Bermudas. 



KET TO THE AMERICAN .SPECIES OF THE GENUS PLATYPODIA 



A'. Carapace not coarsely granulate near the margins. Lobules almost smooth 

 and naked. Mesogastric region narrow, tapering to a slender point. 



spectabilis, p. 247. 

 A^. Carapace coarsely granulate near the margins. Mesogastric region some- 

 what constricted at middle of its length ; extremity not acuminate. 

 B'. Lobules irregular in shape, not surrounded by a furry coat. Protogastric 



lobules two, a large outer, a small inner one rotundata, p. 248. 



B^. Lobules mostly round, finely and crisply granulate, standing out from a 

 background of hair. Only one protogastric lobule on each side. 



gemmata, p. 249. 



ANALOGOUS SPECIES OF PLATYPODIA ON OPPOSITE SIDES OF THE CONTINENT 



Atlantic Pacific 



spectaMlia rotundata 



