136 Bulletin of the Brooklyn Entomological Society Vol. XVI 



While these observations were being made the other Cymatia 

 also captured and fed upon a Corefhra larva. • The details of 

 feeding were essentially the same in this case as in the other. 

 During the time when they were under my observations, about 

 ten weeks in all, the two Corixids continued to feed upon the 

 Corethras, each one taking about one each day, on an average. 

 I also observed them strike at Entomostracans several times, but 

 I can not say whether these were eaten or not. 



There is nothing in these observations, of course, which proves 

 that Cymatia americana is not herbivorous as well as carnivorous ; 

 and Hungerford has stated that even the forms which are pri- 

 marily herbivores will, under extreme conditions, attack Chiro- 

 nomus larvae and small worms, and it may well be that this is 

 such a case. Further observations on the food habits of Cymatia, 

 especially in summer, are necessary to decide this point. How- 

 ever, in view of the predaceous adaptations of the palae, I am 

 inclined to believe that Cymatia is primarily predatory. It may 

 be worth mentioning that the pond from which all my Minnesota 

 specimens of Cymatia americana were taken has a large Corethra 

 population. 



These studies of Cymatia were undertaken at the Entomologi- 

 cal Laboratory of the University of Minnesota, under the direc- 

 tion of Professor Royal N. Chapman, to whom I wish to express 

 my appreciation for his active interest in them, as well as for his 

 valued assistance in the field work during the winter of 1919- 

 1920. 



Food Plant of Cymus discors Horv. — This, bug was found in 

 White Plains, N. Y., on the sedge Scirpus polyphyllus Vahl. 

 on September 10. The insect breeds in the seed heads, now 

 ripe and fuzzy, and was found concealed in them, from the 

 2d or 3d instar to the freshly transformed adult, two or three 

 in each cluster of seeds. Each head harbored from twenty up. 



J. R. de la Torre-Bueno. 



