﻿OF THE STATE ENTOMOLOGIST, 23 



damage to all kinds of cereals and grasses. la 1866 they were quite 

 bad and also in 1870 and 1871, while during the dry years of 1872 and 

 1873, they spread pretty much all over the State and were injurious 

 in counties like Scott, Greene and Mississippi, where they had scarcely 

 been noticed before. 



" We may safely conclude that the Chinch Bug has always existed 

 in Missouri, in small numbers; but that it did not multiply to an 

 injurious extent until the grains began to be cultivated on an exten- 

 sive scale. At all events, we know from the evidence of Dr. Harris 

 and Dr. Fitch, that it existed long ago in exceedingly small numbers 

 in New York, and even in Massachusetts. What the causes may 

 have been that thinned out the numbers of this insect in former 

 times in the West, is another question. In former times, the great 

 bulk of these bugs were probably destroyed every winter by the 

 prairie fires, and, as cultivation has extended in consequence of the 

 country being gradually settled up, and less and less prairie has been 

 annually burnt over, the number that has survived through the win- 

 ter to start the next year's broods has annually become greater. If 

 these views be correct, we may expect them, unless more pains be 

 taken to counterwork and destroy them, to become, on the average 

 of years, still more abundant than they now are, whenever prairie 

 fires shall have become an obsolete institution; until at last Western 

 farmers will be compelled, as those of North Carolina have already 

 several times been compelled, to quit growing wheat altogether for a 

 term of years. 



" It may be very reasonably asked, why the Chinch Bug does not 

 increase and multiply in Massachusetts and New York, seeing that it 

 existed there long ago, and that there are, of course, no prairie fires 

 in those States to keep it in check. The answer is, that the Chinch 

 Bug is a Southern, not a Northern species ; and that hundreds of 

 Southern species of insects, which on the Atlantic seaboard only 

 occur in southerly latitudes, are found in profusion in quite a high 

 latitude in the Valley of the Mississippi. The same law, as has been 

 observed by Professor Baird, holds good both with Birds and with 

 Fishes."* 



The Chinch Bug will, also, for reasons which will presently be 

 made apparent, naturally thrive less in the moister climate of the 

 New England States. Again we may very naturally infer that the 

 more cleanly and careful system of culture, and the more general use 

 of the roller in the older States have had much to do with the com- 

 parative immunity they enjoy. I am also of the opinion that it will 



•Silliinan's Journal, XLI, p. 87. 



