hungerford: aquatic hemiptera. 249 



material being of plant origin. The presence of long filaments 

 of Spirogyra, Zygnema and Oscillatoria cannot be accounted 

 for in any incidental manner. The deliberate action of the 

 bug in feeding on the chlorophyll of Spirogyra, as indicated 

 above, is conclusive evidence of the herbivorous tendencies of 

 these creatures. The presence of oligochgetes, nematodes, roti- 

 fers and protozoa indicates that they consume the little ani- 

 mals along with the plant matter. As a basis for the propa- 

 gation of Corixids in artificial quarters, it has been discovered 

 by experiment that a satisfactory food supply can be obtained 

 by grinding the water-soaked leaves of cattail that have laid 

 in the marsh over winter and allowing them to reach a state 

 of balance. A brown flocculent mass is thus produced, in which 

 develop a flourishing population of tiny organisms, both plant 

 and animal. In such a culture Pahnacorixa has been carried 

 from egg to adult. 



