COLOR PLATE L 



Fig. 1. Filaments of Spirogyra before being fed upon by a Corixid. 



Fig. 2. The same after being fed upon by the bug. Note the empty 

 filaments. 



Fig. 3. An adult Corixid. (Water boatman.) 



Fig. 4. A highly magnified portion of the Spirogyra shown in figure 2. 

 Note the punctured and empty cells. 



Fig. 5. The stomach contents of a small Corixid nymph after thirty 

 minutes feeding on Spirogyra. 



The above illustrations form conclusive proof of the herbivorous tastes 

 of the water boatmen, and modify the frequent assertions of textbooks 

 and serials that "All aquatic Hemiptera are predaceous." 



The colored drawings on these three plates were made by Miss Ellen 

 Edmonson. 



-1669 



