77 
inch long. Many such cocoons are placed side by side, and 
thus form plainly visible masses fastened to the infested plants 
or upon other objects in their vicinity. Fig. 89 shows a species 
of Apanteles bred from the army-worm, a single cocoon, and a 
large number of them crowded together. 
Such cocoons should not be destroyed, as the small wasps is- 
suing from them are our bestfriends. As early as the autumn 
of 1881 the writer introduced these parasites from Europe, 
where they did wonderful execution in the cabbage fields 
crowded with caterpillars. 




Fig. 39.—Apanteles. n. sp., greatly enlarged, the line below showing natural size; its 
cocoons, natural size, fastened upon leaf. and also a single cocoon greatly enlarged. 
(Original). 
Many pups of both species of cabbage butterflies are in- 
fested with another parasite, whichis a minute, green wasp 
(Pteromalus puparum Linn.). Large numbers (40-50) of them 
find sufficient food inside a singlechrysalis. Many other friend- 
ly insects come to our assistance and in some seasons are suf- 
ficiently numerous to check our enemies. 
