24. THE CHINCH BUG. 
Although lying externally on their food plants, and notwithstand- 
ing the fact that the young may attack the bases or even the roots of 
some of these, the species is essentially an external feeder, and appears 
while thus engaged almost totally indifferent to possible attacks of 
natural enemies. When not feeding, however, there is at times a 
tendency to hide away under the sheaths of young corn or beneath 
clods of earth or bunches of coarse stable manure, where this has 
been recently appled and left more or less exposed on the surface of 
the ground. The writer has noted this in cases where neither an 
uncomfortable temperature nor wet weather necessitated protection. 
As has been shown in the description of the larval stages, there are 
four molts between the egg and the adult state. Just how the molt- 
ing larve act we have never been able to determine; neither have we 
witnessed pupation, but a fully developed pupa that is ready to molt 
is easily distinguished by its larger size and more tightly fitting skin, 
which is almost shining white on the median ventral surface of the 
abdomen. It now hides itself away, seemingly preferring to get 
under the sheaths of grasses or grains; but if these are not con- 
venient it will crawl under loose clods, or even into crevices in the 
ground. While thus hidden away the pupa skin splits along the 
back and the fully developed adult makes its way out, leaving the 
empty skin behind. These last are very frequently mistaken for 
dead chinch bugs, and, when moldy, the farmer is very likely to sup- 
pose that they are bugs which have been killed by the fungus Sporo- 
trichum globuliferum, if this has been applied in the fields. 
On first emerging from the pupa the adult is generally of a dull 
pink color, except the wings, which are white, exclusive of the veins; 
these being of the same pinkish hue as the body. In a short time 
these colors change to the normal ones of the species, but during the 
breeding season these newly developed adults may be observed crawl- 
ing about with the young of all stages as well as the maturely colored 
adults. 
If this development has been taking place in a wheat field and the 
grain is harvested at this time, or if from any other cause the food 
supply becomes suddenly exhausted, all sizes of larvee with pups and 
adults will start off on foot to hunt for a fresh supply. Though 
many individuals may now have become fully developed, and, so far 
as can be determined, possess wings entirely fitted for active service, 
nevertheless they will crawl along a dusty road or across freshly 
plowed fields in company with their less fortunate fellows, seemingly 
never for a moment supposing that they can span the intervening 
space by flight. The writer is totally unable to account for this phe- 
nomenon in the species at this time, the disinclination to use the wings 
being so wholly unlike the habits of B. doriw, as shown by the careful 
and painstaking observations of Professor Sajé in Hungary. Again, 
