166 Trans. Acad. Sci. of St. Louis. 



35. AL0NA INTERMEDIA SarS. 



Alona intermedia, Herrick & Turner, '95, pp. 244-245; pi. LXIL, 

 fig. 15. 



This species was found on only one occasion; then it 

 was in a marsh having a water temperature of 12° C. 

 The bottom was grassy, the grass was dead. 



36. ALONA CORONATA KurS. 



Alona coronata, Herrick & Turner, '95, p. 247. 



This form was found on only one occasion ; then it was 

 collected, in abundance, from a ditch in a marsh, in Jan- 

 uary, 1908. 



PLEURoxus P. E. Mueller. 



37. PLEUROXUS DENTICULATUS Birge. 



Pleuroxus denticulatus , Birge, '78, pp. 20-21; pi. I., fig. 21. 

 Pleuroxus denticulatus, Herrick & Turner, '95, p. 256; pi. XLV., 

 fig. 8; pi. LXIII., fig. 10a, 12, 13. 



Near Augusta, this species was common, among vege- 

 tation, in certain marshes and no-outlet, permanent, 

 ponds, having a water temperature from 8° C. to 17° C. 



38. PLEUROXUS HAMATUS BirgC 



Pleuroxus hamatus, Birge, '78, pp. 22-23; pi. II., fig. 13, 14. 

 Pleuroxus hamatus, Herrick & Turner, '95, p. 257; pi. LX., fig. 1. 



This species was abundant, among vegetation, in two 

 of the large, no-outlet, permanent ponds ; at a water tem- 

 perature of from 16° C. to 21° C. 



chydorus Leach. 



39. CHYDORUS SPHAERICUS 0. F. M. 



Chydorus sphaericus, Birge, '78, pp. 23, 24. 



Chydorus sphaericus, Herrick & Turner, '95, p. 261; pi. LXIV., 

 fig. 4, 7, 8, 10. 



This species was abundant in several of the no-outlet, 

 permanent, ponds. It was found among vegetation and 

 also where there was practically no vegetation. The 

 temperature of the water in which it was found varied 

 from 10° C. to 29° C. 



