96 Annals Entomological Society of America [Vol. XII, 



cells, each on a Typha leaf near the tip. These two specimens 

 also were brought to the laboratory and placed in the tin box 

 with the other egg. 



On May 28th the first egg had hatched. The young larva 

 had opened one of the other mud balls and devoured the egg 

 within. The third mud ball was then removed to another tin 

 box. The first young larva died two days later, May 3()th. 

 That left only one egg of the lot. This egg hatched on the first 

 of June, six days after it had been brought into the laboratory. 

 The young larva was transferred to another clean tin salve box 

 containing moist, sterilized sand. 



Various kinds of food were offered to the young larva ; larvae 

 and pupae of Lymncscia phragmitella Stainton, larvae of Nonagria 

 oblonga Grote, Arsilonche albovenosa Goeze, and Arzama obliqua 

 Walk. Flies and fresh meat were also offered to the larva. At 

 first the young larva fed somewhat on flies and on larvae and 

 pupae of L. phragmitella, but it showed a decided preference for 

 the little larvae of A. obliqua. 



During the second and third instar all other food was refused 

 except larvae of A. obliqua. 



All the above mentioned Lepidoptera are inhabitants of 

 Typha. A. albovenosa is an incidental surface feeder on the 

 leaves; L. phragmitella lives in the heads of Typha, while 

 A. obliqua and N. oblonga both begin their larval activities as 

 leaf miners, later becoming solitary stem borers. 



It is possible that the lavvse of Chlcenius impunctifrons feed 

 altogether on the larvae of A. obliqua. The former hatch about 

 the same time that the larvae of the latter species leave the 

 mines of the leaves of Typha to become stem borers. Thus 

 while they are exposed they might easily fall prey to the Carabid 

 larvae. 



On June 3, 11:00 A. M., the larva cast its first skin, the first 

 instar having lasted three days. June 6, at noon, the larva 

 molted again. The third instar larva had a voracious appetite 

 and consumed many of the little A. obliqua larvae. Five days 

 later, June 11, the larva had tunneled into the moist sand and 

 hollowed out a little cell. In this cell it was lying on its side as 

 if ready to pupate. Having been disturbed the larva came to 

 the surface of the sand and remained there, lying on its back. 

 Whenever the box was opened it made efforts to turn over 

 but was unable to do so. When turned over the larva crawled 



