THE CHINCH BUG. dial 
THE FROG. 
Dr. Cyrus Thomas quotes Ross and others as stating that the com- 
mon frog is an enemy of the chinch bug. While this is probably true, 
it is nevertheless well known that comparatively few frogs frequent 
grain fields, as a rule, and thus the benefit derived from their attacks 
is of too little importance to merit further notice. 
INSECT ENEMIES. 
Of the invertebrate enemies of the chinch bug the same may be said 
as of the frog. The writer has occasionally found a chinch bug con- 
taining a species of Mermis, or “‘hair snake.’ Occasionally, also, 
ants may be seen dragging these bugs away, while lady-beetles have 
sometimes been found to devour them, as recorded by Walsh and 
Forbes. Perhaps the worst insect enemies of the chinch bug are to 
be found among its comparatively near relatives—the insidious 
flower bug,’ and Milyas cinctus Fab., the latter being reported by 
Thomas as the most efficient of the insect enemies of this pest, while 
Riley found that the former also attacked it. Prof. Forbes ascer- 
tained, by examinations of the contents of the stomach of a ground 
beetle,? that one-fifth of the total food of this species was composed 
of chinch bugs. Shimer and Walsh both claim that lacewing flies * 
destroy chinch bugs, and they are doubtless correct. The writer has 
very often found dead chinch bugs entangled in spider webs, although 
whether killed for food or by accident it has been impossible to 
determine. 
A minute hymenopterous or wasplike parasite of the egg has 
recently been discovered in Kansas by Mr. J. W. McCulloch of the 
Kansas Agricultural Experiment Station, but little is as yet known 
regarding its efficiency as a means of control. 
NATURAL CHECKS OTHER THAN ANIMALS. 
WEATHER CONDITIONS. 
There are two natural checks to the increase of the chinch bug 
other than animal enemies. One of these is vegetable in nature, 
being a fungus, the other meteorological, and the interrelation of the 
two is so close that the former is almost entirely dependent upon the 
latter. It will at once be seen that the chinch bug, occurring as it 
does from but little north of the equator to a latitude of nearly 50° 
north, and from an elevation of more than 200 feet below sea level 
in the Imperial Valley of southern California to upwards of 6,000 
feet above sea level in the mountainous regions, must be able to 
withstand almost every conceivable variation of climatic conditions. 
1 Triphleps insidiosus Say (Anthocoris pseudo-chinche of Fitch’s Second Report). 
2 Agonoderus pallipes Fab, 
3 Chrysopa spp. 
