576 -PROCEEDINGS OF THE NATIONAL MUSEUM. vol.xxiii. 



76. ACTONISCUS Harger. 

 i8o. ACTONISCUS ELLIPTICUS Harger. 



Adon'mcus (jllii>tiras\lAn(rV.K, Am. Jour. 8fi., XV, 187S, p. .S7o; Proc. U. 8. Nat. 



Museum, II, 1879, p. 159; Rep. U. S. Fish Comm., 1880, Pt. 6, p. 309-310, 



pi. I, fig. 3. 

 Armadilloniscus eUipticm Budde-Lund, Crust. Isop. Terrestria, 1885, ji. 239. 



Habitat. — Savin Rock, near New Haven, Connecticut; Stony Creek, 

 Long Island Sound. 



Depth. — Found on beach. 



On Sars's authority I have retained this genus with the TrtchonlscidcB, 

 where he placed it. 



77. SCYPHACELLA Smith. 



i8i. SCYPHACELLA ARENICOLA Smith. 



SciiphaceUa ((irnlcola Smith, Rep. U. 8. Fish Comm., Pt. 1, 1874, p. 568 (27-4). — 

 Verrill, Rep. U. S. Fish Comm., Pt. 1, 1874, p. 337 (43).— Harger, Proc. 

 U. S. Nat. Museum, II, 1879, p. 157; Rep. U. S. Fish Comm., 1880, Pt. 6, 

 p. 307-308, pi. I, fig. 2. (See Harger for synonymy.) 



Trichoniscus arenkola Budde-Lund, Crust. Isop. Terrestria, 1885, p. 249. 



Ilahitat. — Egg- Harbor, New Jersey; Nobska Beach, Vineyard 

 Sound; Nantucket Island. 



Dej)th. — Found on beach. 



Sars places Scyjyhacella with the Trie/ajn/'-scidw., where, following his 

 authority, I have retained it. 



VI. EPICARIDEA or BOPYROIDEA. 



ANALYTICAL KEY TO THE FAMILIES OF EPICARIDEA. 



(1. Body of female distinctly segmented, more or less asymmetrical, twisted either to 

 right or left. Maxillipeds lamellar, biarticulate, and more frequently exhil)it- 

 ing a small terminal joint. Legs in seven pairs, sometimes obsolete on one 

 side. Inculpatory plates five pairs, more or less arching over the ventral sur- 

 face of the thorax. Pleopoda forming simple or double lamelUe, all of the 

 same structure, rarely obsolete. Male vi^ith all the segments of the thorax 

 sharply defined. Last larval stage with the flagelluni of the antennte four 

 articulate; legs of uniform structure; uropoda with inner branch shorter than 

 outer. Parasitic on decapodous Crustacea . Family XXIII. Bopyrid^ (p.577). 



(/. Body of female perfectly symmetrical, the segmentation, as a rule, only visiljle 

 in the middle of the dorsal face. Maxilliiieds lamellar, without any terminal 

 joint. Only five pairs of legs present. Incubatory plates comparatively 

 small, sometimes greatly reduced in number, and scarcely at all partaking of 

 the formation of the marsupium, which constitutes two separate cavities 

 bounded T)y the lateral walls of the body itself. Pleopoda generally rudimen- 

 tary or'wholly absent. Male with head and first segment of thorax coalesced. 

 Last larval stage with the flagellum of the antennas five articulate; legs of the 

 first pair shorter and thicker than the others; uropoda with the branches sub- 

 equal. Parasitic on Schizupmhi Family XXIV. Pajid^ (p. 579). 



