58 BULLETIN 166, UNITED STATES NATIONAL MUSEUM 



small tooth is sometimes present. Antennal flagella longer than 

 carapace. External maxillipeds with a marked pediform cast. 

 Chelipeds equal, slender, though stouter than legs. First two pairs 

 of legs much longer than the chelipeds; last two pairs much shorter 

 than the first two pairs, subdorsal, prehensile. Abdomen in both 

 sexes consists of seven separate segments; no lateral platelets inter- 

 calated between the sixth and seventh segments. Gills trichobran- 

 chiae or intermediate between trichobranchiae and phyllobranchiae ; 

 gill-plumes very numerous — there may be as many as 20 on either 

 side. Epipodites on the chelipeds and first two or three pairs of 

 legs. Sternal grooves of lemale short, ending at level of genital 

 openings. (After Alcock.) 



KEY TO THE AMERICAN GENERA OF THE FAMILY HOMOLODROMIIDAE 



A'. Carapace subquadrate. Antennules not concealed. Ambula- 

 tories very long and slender Homolodroinia (p. 58) 



A2. Carapace ovoid. Antennules folding under rostral teeth. 



Ambulatories short Dicranodromia (p. 59) 



Genus HOMOLODROMIA A. Milne Edwards 



Homolodromia A. Milne Edwards, Bull. Mus. Comp. Zool., vol. 8, p. 32, 1880 

 (type, H. paradoxa A. Milne Edwards). — Bouvier, Bull. Soc. Philom. 

 Paris, ser. 8, vol. 8, p. 37 [4], etc., 1896. — A. Milne Edwards and Bouvier, 

 Mem. Mus. Comp. Zool., vol. 27, p. 9, 1902. 



Carapace narrow, wider behind than in front. The antennules 

 are too large to fold into their fossettes. Antennae very mobile, 

 inserted below the ocular peduncle; they are much longer than the 

 carapace. The ej^es are very small and have no special orbital 

 cavity. Buccal area quadrilateral; epistome very distinct. Teeth 

 of fingers sharp, fitting together. The first and second ambulatories 

 are slender and very long, the third and fourth pairs are elevated on 

 the dorsum, small and cheliform. Abdomen of male composed of 

 seven segments, which are in contact only in their middle part, their 

 lateral parts narrower and free. 



West Indies; east Africa; 356 to 472 fathoms. 



HOMOLODROMIA PARADOXA A. Milne Edwards 



Plate 13, Figures 1, 2; Plate 14, Figures 1-4 



Homolodromia paradoxa A. Milne Edwards, Bull. Mus. Comp. Zool., vol. 8, 

 p. 33, 1880 (type locality, off Nevis, 356 fathoms; type in M. C. Z.); Pvccueil 

 de figures de Crustac^s nouveaux ou peu connus, pi. 6, figs. 2-2e, 1883. — 

 Bouvier, BuD. Soc. Philom. Paris, ser. 8, vol. 8, p. 38, etc., figs. 1, 2, 3, 32, 

 189G. — A. Milne Edwards and Bouvier, Mem. Mus. Comp. Zool., vol. 

 27, p. 11, figs. 1, 2, pi. 1, 1902. 



Diagnosis. — Ej^es small, without special orbital cavity. Last two 

 pairs of legs with cheliform extremities. 



