THE CRUSTACEA OF NEW JERSEY. 63 



Remarks. — This little crustacean is very valuable as foo(^ for 

 many of our fresh-water fishes. It is also in demand by breeders 

 of aquarium fishes, as forming food for the fiy, especially those 

 of the gold fish with its ornamental varieties. It appears to be 

 common only periodically, and especially during the spring of the 

 year or in the month of May. At this time it may be seen in 

 great abundance in the ditches about Camden and Philadelphia, 

 the myriads of individuals often imparting to the water a bloody 

 appearance. The color varies from perfectly transparent to the 

 deepest dull red, though the former condition is the most usual 

 in which individuals are found most of the year. It is widely 

 distributed, occurring in many parts of. the United States and 

 Europe. 



Genus SCAPHOLEBERIS Schoedler. 



Scapliolebei'is Schcedler. Die Branchipod, Berlin, 1858, p. 23. Type Daphne 

 mucronata Miiller. (Not consulted.) 



Body robust, continuation of fornices extending toward apex 

 of incurved beak, which usually lies within valves of shell. Lower 

 posterior angle of shell angled or spined. Lower anterior angle 

 of shell with a prominence and a basin-shaped area encloses base 

 of antennse, latter partly lying on shell and part on head. This 

 area more strongly lined or reticulated than rest of shell. Lower 

 margin straight and ends usually in a long scythe-shaped spine 

 which directs backward. Shell usually indistinctly reticulated or 

 umnarked, and usually deeply colored. Post-abdomen similar to 

 that of Ceriodaphnia or Shnos, with anal spines few and older 

 specimens having more than young, and place where additional 

 spines are to appear marked by prominences. Eye moderate in 

 size, pigment fleck rather small and short antennules hidden 

 by beak. Antennae of small size and generally dark colored. 

 Ephippium containing but one tgg. Males without altered 

 antennae or feet. 



Key to the species. 



a. Shell with short spine at lower posterior corner. mucronata 



aa. Shell with a long spine at lower posterior corner. armata 



