FIG. 56. Some fresh- water crustaceans: a, Asellus, the water sow bug; 

 b, Gammarus, the bender; c, Palaemonetes, the true shrimp; d, Eubranchipus, the 

 fairy shrimp; e, Cantho campus; f, Cyclops; g, Cypris, side and top views; h, 

 Daphnia, the water flea. 



