CACTUS-FEEDING INSECTS AND MITES 153 



Volucella spinigera, Argentina, Peru. 



Voliicella scutellata, Argentina. 



Copestylum marginatum^ Texas, Arizona, Mexico. 

 Other species reared from prickly pear are: 



Volucella avida, Texas, Arizona. 



Volucella satur, Colorado, New Mexico. 



Volucella fornax, Arizona. 



Volucella fraudulenta, Colorado. 



Volucella deceptor, Mexico. 



Volucella 2 sp., Mexico. 



Volucella eugenia, Jamaica. 

 Although the adult flies were freely attracted to cages containing other 

 prickly pear insects and deposited eggs on the cages and on any heaps 

 of decaying cactus, reared material could not be induced to oviposit 

 under any conditions of confinement, from small glass and other vessels 

 to large wire enclosures. 



The same difficulty was experienced with flies of the stratiomyid 

 genus Hermetia: H. aurata, H. hunteri, and H. illucens, which are very 

 common cactus scavengers in North America. 



