STALK-EYED CRUSTACEA 473 



base, tapers to the apex. First and second pair of legs 

 short; pincers fringed with hairs. Third pair large and 

 long; fourth and fifth pair robust, shorter than the third. 

 Abdominal appendages short, broad, and foliaceous. 

 Swimming organ short, robust, and well developed. The 

 telson is shorter than the lateral plates. The internal 

 antennae have two flagella ; the external have a basal 

 scale and a long flagellum. 



Range. — ^Fresh-water rivers and ponds of West Indies, 

 Mexico, Cape Verde Islands, New Caledonia, New Zealand, 

 and Fiji. 



I. Atya scabra. 



Atja scabra . . Leach, Desmarest, Roux, H. Milne 

 Edwards. 



Rostrum triangular, armed with three small parallel 

 ridges, of which the middle one is the longest. The 

 gastric region is a little rough. The two first pairs of 

 legs do not exceed the peduncles of the external antennae. 

 Those of the last three pairs are rough, with small points. 

 There are two series of small spines upon the telson. 



Range. — West Indies, Mexico. 



Family II. Acanthephyridse. 



AcanthepliyridcT; . . . Spence Bate. 



Animal smooth, laterally compressed, and dorsally 

 carinated. Internal antennae with two long flagella. 

 External antennae with a sharp and rigid basal scale. 

 Mandibles with a palp. First two pairs of legs slender, 

 subequal, and armed with pincers. 



Telson long, narrow, and tapering to a truncated 

 point, 



