(22) 



A. hrcvicauda, Forbes. Head with hind angles laterally extended, 

 forming broad spinous lobes ; front angles of first thoracic segment notched, 

 no lateral notches on thoracic segments ; tip of abdomen with broad rounded 

 lobe, pedicels of caudal stylets as broad as long, palm of hand with two 

 strong spines. 



A. intermedim, Forbes. Head with small lateral lobes. First thoracic 

 segment with front angles entire, others notched laterally ; hind angles of 

 abdomen not distinct, pedicel of caudal stylet twice as long as wide. 



A. stygm?, Packard. Slender, loosely-jointed, colorless and blind: 

 caudal stylets slender, cylindrical, abdomen not lobed behind. 



ORDER PHYLLOPODA. 



Feet, ten to sixty pairs, broad and flat, two or three-lobed ; mouth with 

 mandibles and maxillae, antennae usually small, not used for swimming. 



FAMILY BRANCHIPODICAE. 



Body long and slender, no carapace, thoracic segments distinct, eyes on 

 stalks, second antennae converted into clasping organs. Eleven pairs of 

 gill-feet. Female with egg-pouch at base of abdomen. 



Genus Eubrunchipus. 



Head large, claspers ' 21) of male thick and strong, with a tooth at base of 

 second joint ; a pair of simple, flat, serrate, membranous appendages attached 

 to front of head ; caudal appendages long, lanceolate, with many fe.thery 

 hairs. Egg-pouch short, thick, broad-oval. 



F. serratus, Forbes. Frontal appendages longer than claspers, irregu- 

 larly ovate, deeply serrate. Tip of claspers flattened within, abdomen 

 somewhat serrate. 



FAMILY ESTHERIADAE. 



Compressed ; head and body enclosed in a bivalve shell. Eyes sessile ; 

 feet, ten to twenty-seven pairs. 



Genus Limnetis. 



Shell circular, globose, no beaks or lines of growth. Inner antennae 

 two-jointed ; feet ten or twelve ; abdomen truncate. 



ORDER CLADOCERA. 



Body enclosed in a bivalve shell, head free ; abdomen acutely forked; 

 eye single, large. Lower antennae form large branched swimming organs ; 

 feet four to six pairs. 



FAMILY DAPHNIADAE. 



Upper antennae minute, one or two-jointed : five pairs of feet, all en- 

 closed by carapace. Intestine nearly straight. 



ORDER OSTRACODA. 



Biting mouth, one eye, two pairs of antennae, one for swimming; bi- 

 valve carapace enclosing head and body. Feet one to three pairs. 



