14 Farmers’ Bulletin 1223. 
disease is already present, its destructiveness can noi be increased by 
introducing more diseased material; and where not present, intro- 
duced disease has no noticeable afteat as its absence means conditions 
unfavorable to the fungus. 
Another disease ** which probably attacks the chinch bug has been 
known since 1888, when it was first discovered in cutworms. In the 
last three years it has been found attacking a number of different 
kinds of insects, and its possible usefulness is still under investi- 
gation. | 
PREDACIOUS AND PARASITIC ENEMIES. 
While the chinch bug has a considerable number of enemies be- 
longing to the animal kingdom, it is more fortunate than most other 
insect pests in escaping attack, and, for an insect of such great abun- 
dance and wide distribution, has comparatively few natural enemies. 
None of them appears to prey wholly or even to a large extent upon 
it alone; none of them appears to be of any great importance in sup- 
pressing serious outbreaks. The birds and other higher animals 
which have been known to eat chinch bugs feed upon almost all 
kinds of insects, and thus destroy only an occasional individual of 
this kind. 
Its most important natural enemies are undoubtedly other insects, 
twenty or more kinds of which are known to attack it occasionally 
or habitually. The most important of these are lady beetles, ground 
beetles, true bugs, the young of the lace-winged flies, and ants. A 
great majority, if not all of them, feed widely upon many kinds of 
insects, and are by no means especially destructive to chinch bugs. 
The most important predatory enemies are probably the insidious 
flower bug,** the many-banded assassin bug,?° and several kinds of 
ants. Both the insidious flower bug and the assassin bug, however, 
have a multitude of other victims, and even when numerous among 
the chinch bugs have never been seen noticeably to reduce their 
numbers. The false chinch bug,?® which often occurs on field and 
garden crops in extremely large numbers, also feeds occasionally on 
young chinch bugs, but it is almost entirely a plant-feeding insect. 
Ants are more numerous than all other animals put together and 
probably cause the death of more chinch bugs than any other enemy. 
Only two truly parasitic insects, living within the body of their 
host, assail the chinch bug. One of these is known as the chinch-bug 
egg parasite,” and has been credited at one time with annihilating 
ou 16 to 50 per cent of the eggs in Kansas. The other is a wasp- 
like insect,?* whose habit of parasitizing chinch-bug eggs has been 
discovered, but of which little further is known. 
23 Sorosporella uvella (Krass.) Gd. 26 Nysius angustatus Uhl. 
4% Triphleps insidiosus Say. 27 Humicrosoma benefica Gahan. 
% Milyas cinctus Fabr. 23 Abbella subflava Gir. 
