454 STALK-EYED CRUSTACEA 



directed tooth, and on the sixth with a posteriorly 

 directed one. Telson tapering, dorsally depressed, and 

 nearly equalling the lateral branch of the swimming 

 organ in length. 



Range. — St. Thomas, Bahia. 



3. Benthesicymus. 



BentJicsicyums .... Spence Bate. 



Body smooth. Rostrum short, elevate'd into a crest. 

 Cervical fossa deeply marked ; a strong calcified ridge 

 separates the lateral cardiac from the branchial region. 

 Posterior segments of the abdomen, laterally compressed, 

 are shorter than the branches of the swimming organ. 

 The telson is narrow, pointed, and laterally compressed. 

 The abdominal appendages are long, and, except the 

 first pair, two-branched. In the male the basal joint of 

 the first pair has a membranous appendage. 



The internal antennae have outside a spine, but inside 

 there is no appendage. There are two long flagella. The 

 external antennae have a long slender flagellum. The 

 third basal joint has a hook-like process which is lodged 

 in a depression on the under surface of the internal 

 antenna. The epistome is produced to a point. The 

 maxillipedes have external appendages. 



Each leg has a basal appendage which diminishes 

 posteriorly. All the first joints of the two maxillipedes 

 and the four first legs have branchial plates that increase 

 in size, each with a branchial plume. There are gills 

 from the chest wall, and from all the membrane between 

 the body and the first joint of all the limbs, except the 

 last pair. 



Range. — Atlantic and Pacific Oceans ; in deep 

 water. 



