294 REPORT OF NEW JERSEY STATE MUSEUM. 

 Super-Family TANAIOIDEA. 



Body usually slender, nearly cylindrical. Cephalon fused with 

 first, also sometimes second, segment of thorax, to form cara- 

 pace, and latter with small branchial cavity on each side. Other 

 six segments of mesosome well defined, with small or inconspic- 

 uous coxal plates. Metasome generally of four segments, first 

 five short, subequal, and last much largest. Eyes distinct or ab- 

 sent. First antennae generally simple, sometimes with one or 

 two flagella. Second antennae smaller than first, issue immie- 

 diately below. Mandibles with or without palps. First maxillae 

 with reflexed setiferous palp, placed in hind part of carapace. 

 Second maxillae very small, often rudimentary. Maxillipeds 

 mostly coalesced at base, with four- jointed palp and larg-e back- 

 wardly directed membranous epignath which passes into 

 branchial cavity. First pair of legs very strong, curving anterior- 

 ly, and each ends in cheliform hand. Second pair sometimes 

 unlike succeeding pairs, which latter simple and ambulatory. 

 Pleopoda, when present, comparatively small, natatory, and rami 

 lamelliform. Uropoda terminal, of four short basal segments 

 and one or two filamentary branches. Sexual differences fre- 

 quently pronounced. 



A single family within our limits. The Apseudidae is the only 

 other famil}' belong-ing to this group, known sometimes also as 

 the Chelifera. 



Family TANAID^. 



Body sublinear, cylindrical, scarcely attenuated behind. Cepha- 

 losome not very broad, scarcely depressed, and front usually 

 narrowly truncate. Ocular lobes sometimes well defined, some- 

 times obsolete. Free segments of mesosome perfectly smooth, 

 and middle ones generall}^ the longer. Coxal plates inconspic- 

 uous. Metasome comparatively short, scarcely narrower than 

 mesosome. Eyes present or absent. First antennae issue close 

 together from frontal part, simple. In female first antennae com- 



