VI 



PARASITES — COLLECTING 



WE have stated that parasitic flies prey upon the 

 early stages of moths, some on the eggs and 

 some on the larvae. Some of these flies are Hymenop'- 

 tera, that is, "membrane-winged," with four clear 

 wings, the fore wings being the larger. The females 

 have ovipositors which can pierce an egg-shell or the 

 skin of a caterpillar. 



Thanks to the kindness of Dr. William H. Ashmead, 

 we can give the names of the Hymenoptera which 

 attack the eggs and larvae of the SpMng'idfP, Cerato- 

 camp'idcc, and Saturni'ldce. 



Tele'nomus sph'mg'is, Ashm., and Anasta'tus pear'- 

 salli, Ashm., pierce the eggs and lay their own eggs in 

 them. Of course they must be very tiny flies, or their 

 larvae could not find in these small eggs food enough 

 to enable them to grow up, pupate, and emerge as flies, 

 one or more in each moth egg. 



We have found mats of very small eggs on leaves, 

 and hoped for some new crawler, only to have pieces 

 of the shells lift and tiny black flies emerge from the 

 whole mat, not one egg being overlooked by the busy 

 fly-mother. 



66 



