GENERAL REFERENCES 



Birge, E. A. 1918. The Water Fleas (Cladocera). Chap. 22 in Ward and 

 Whipple's "Fresh-water Biology". John Wiley ^ Sons. New York 



Herrick, C. L. and Turner, C. H. 1895. Synopsis of the Entomostraca of 

 Minnesota. Second Report of the State Zoologist. Geol. & Nat. Hist. 

 Surv. of Minn. 



KEY TO SOME OF THE MORE COMMON GENERA 

 OF OSTRACODS 



1. Last pair of legs directed downwards and used in moving about 2. 

 Last pair of legs directed backward and not used in moving about 



Family Cypridae 4. 



2. With two pairs of legs; Family Darwinulidae 



Darwinida Brady & Robertson 

 With three pairs of legs; Family Cytheridae 3. 



3. Shell smooth and thin; parasitic on gills of Crustacea 



Entocythere Marshall 

 Shell rough; not parasitic 



Limnocythere Brady 



4. Second antennae with spines and claws at tips but no swimming setae; 



non'swimming animals 

 Candona Baird 

 Second antennae with swimming setae and terminal spines and claws; 

 swimming animals 5. 



5. Second leg ending in three tips, one or two of which are bent back to- 



wards the base of the leg 

 Cypria Zenker 

 Second leg ending in one or more short curved projections resembling a 

 beak and one long spine or claw directed ahead away from the leg 6. 



6. Caudal ramus with one long slender tip, besides the short basal spine 



Cy pridopsis Brady 

 Caudal ramus with terminal claws or setae or both 7. 



7. Swimming setae on second antennae as long as the terminal spines and 



claws 



Eucypris Vavra 

 (Cypris Miiller) 

 Swimming setae shorter 



Chlamydotheca Saussure 



GENERAL REFERENCES 

 Herrick, C. L. and Turner, C. H. 1895. Synopsis of the Entomostraca of 



Minnesota. Second Report of the State Zoologist. Geol. & Nat. Hist. 



Surv. of Minn. 

 Hoff, C. C, 1942. The Ostracods of lUinois. Ill Biol. Monog. 19, Nos. 1 



and 2. 

 Sharpe, R. W. 1918. The Ostracoda. Chap. 24 in Ward and Whipple's 



'Trcsh'water Biology". John Wiley & Sons. New York. 

 Turner, C. H. 1899. Synopses of North American Invertebrates — Fresh 



Water Ostracods. Amer. Nat., Vol. 33. 



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