46 REPORT OF NEW JERSEY STATE MUSEUM. 



Key to the genera. 



a. Frontal appendages present; ovisac short, broad. 



b. Frontal appendages ribbon-like or broadly triangular, eubr-^nchipus 



bb. Frontal appendages long and variously lobed or spinulose. INO 



•aa. No frontal appendages; ovisac long and slender. strEptocephalus 



Genus EUBRANCHIPUS Verrill. 



The Fairy Shrimps. 



Mubranchipus Verrill, Froc. Amer. Assoc. Adv. Sci., XVIII, 1869, p. 241. 

 Type Branchipus vernalis Verrill, first species. 



Male. — ^Body large, very stout, robust. Head large, with 

 •elbowed claspers large, thick, stout, complex, form quite vari- 

 able, two-jointed. First joint of clasper very stout, thick, nearly 

 straight, with stout inward-pointing spine at base. Second joint 

 v^aries in form., usually simple and straight, chitinous, bent a 

 little at tip, stout at base. Head with pair of frontal append- 

 ages, hanging down between claspers, forming two broad,- 

 flat triangular lobes with crenulated edges, or very large and 

 deeply and finely lobulated. Eleven pairs of natatory feet, usually 

 fifth endites rather large and edge not very square but rather 

 pointed. Penis large, broad, slightly cleft, cirrus long and 

 slender. Caudal appendages long, slender, nearly twice as long 

 as in Branchinecta. 



Female. — ^Body long. Head large. Caudal appendages as in 

 inale. Egg-sac short, broad, bottle-shaped, opening transverse, 

 at end of short neck. 



This genus is perhaps the most familiar of all the phyllopods. 

 Packard points out several distinctions between the European 

 form, Branchipus stagnalis (Linnaeus), and Bubranchipus verna- 

 lis (Verrill) of our own country, which appears of general value. 

 The former has simple, long, slender filiform frontal appendages 

 and a deeply cleft penis. The latter species has broad, flat, tri- 

 angular lobate frontal appendages with crenulated edges and a 

 slightly cleft penis. 



