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Pomona College Journal of Entomology 



produce more eggs and to thereby destroy more insects. The life-cycle varies 

 according to the time of year. In the colder months it covers from about ninety 

 to one hundred days, while during the summer months it covers from eight to fifteen 

 days. 



Thi: so-called "Mummied" plant lice (Figure 205) are easily recognized 

 before the adult parasite escapes by the inflated and discolered bodies which appear 

 among the healthy individuals. These bodies are usually of a lighter color and 

 finally become entirely bleached. The circular hole cut by the escaped parasites 

 is always a sure sign of the presence of these beneficial insects. The "mummies" 

 are fastened to the leaf, as soon as the louse is dead, by the larva of the parasite, 



Figure 205 



Mummied bodies of parasitized plant lice. 



which cuts a slit in the lower side of the body and fastens the sides to the 

 leaf or twig by excreting a mucilageous or web-like substance for this purpose. 



So far, I have been able to collect two distinct forms of these hymenopterous 

 parasites — one a very common Braconid, Aphidlus testaceipes Cresson, and the 

 other a C'yniiiid of the genus Charips {AUotria). Brief descriptions of those 

 insects are as follows : 



Aphidius testaceipes (Cresson) 

 (Figure 206, left) 

 1879 Trioxys testaceipes (Cresson) Comstock, U. S. Dept. Agrcl. Rept. 



p. 208. Original description. 

 1888 Lysiphlebus testaceipes (Cresson) Ashmead, Proc. U. S. Nat. Mus. 

 p. 667. 



