30 BULLETIN 166, UNITED STATES NATIONAL MUSEUM 



its apex usually in close contact with the deflexed tip of the front. 

 Fingers of cheHpeds generally short, stout, and strongly calcified in 

 their distal half. The abdomen of both sexes consists of seven 

 separate segments. Many species are protected by a commensal 

 sponge or ascidian, or by a valve of a lamelUbranch shell. (After 

 Alcock.) 



KEY TO THE FAMILIES OF THE SUPERFAMILY DROMIIDEA 



A*. Vestiges of sixth abdominal limbs present (except in Ilypoconcha, 



where also no mastigobranchs) . Carapace usually not longer 



than broad, with well-marked side edge. 



B^ Mastigobranchs on first legs (chelipeds) only or on none. 



Fourth and fifth legs small, subdorsal, and usually prehensile. 



Dromiidae (p. 30) 

 B^. Mastigobranchs on all of first three pairs of legs. Fifth legs 



only small and subdorsal Dynomenidae (p. 51) 



A2. No vestige of sixth abdominal limbs. Carapace longer than 

 Vjroad, with ill-marked side edge. First three legs with 

 mastigobranchs, fourth and fifth small, subdorsal, and pre- 

 hensile Homolodr omiidae (p. 57) 



Family DROMIIDAE Alcock 



Dromiidae Alcock, Journ. Asiatic Soc. Bengal, vol. 68, p. 128, 1899. — Schmitt, 

 Univ. California Publ. ZooL, vol. 23, p. 183, 1921. 



Carapace subglobular, rarely flattened; no lineae anomuricae (a 

 pair of longitudinal suture lines on the carapace) ; sternum of female 

 traversed for more or less of its extent by two obliquely longitudinal 

 grooves. External maxillipeds generally operculiform. Legs of 

 moderate size, fourth and fifth pairs short, subdorsal in position, and 

 furnished with a small, hookhke nail or dactyl. Sixth segment of 

 abdomen generally with rudimentary uropods. (Schmitt.) 



KEY TO THE AMERICAN GENERA OF THE FAMILY DROMIIDAE 



A'. Carapace convex, pilose. 



B^. Sternal sulci of female produced to segment of chelipeds, and 



approximating in a tubercle Dromidia (p. 32) 



B^. Sternal sulci of female produced to segment of second pair 



of feet and not approximate Dromia (p. 30) 



A^ Carapace flat, membranous above Hypoconcha (p. 44) 



Genus DROMIA Weber 



Dromia Weber, Nomenclator entomologicus, p. 92, 1795 (type, Cancer dromia 

 Fabricius, 1793). — Fabricius, Supplementum entomologiae sj'^stematicae, 

 p. 359, 1798. — Milne Edwards, Histoire naturelle des Crustaces, vol. 2, 

 p. 170, 1837.— Stimpson, Proc. Acad. Nat. Sci. Philadelphia, 1858, p. 226 

 [64]. 



Carapace transverse, convex, pilose. Palate smooth. Sternal sulci 

 of female not approximated, produced to segment opposite second 



' Evius (E. ruber Moreira, Bull. Soc. Ent. France, no. 15, p. 322, fig. I, 2, 1912) may be the larval stage o( 

 Dromia erythropus. The original figures I and 2 have been reproduced on pi. 8. 



