1 54 Cincinnati Society of Natural History. 



but not elsewhere east of the Rocky Mountains, so that we may 

 safely assume that it entered the United States in extreme southern 

 Texas, precisely as was probably the case with Blissus leucopterus. 

 From Washington county, Texas, the species now under consideration 

 spread northward to Denver, Colorado, where it was observed by 

 Mr. Uhler in 1876, and is also recorded the same year from Missouri, 

 by Riley, and also from Delaware. In 1890 it was first noticed in 

 Southern Indiana, and in Ohio as previously stated, and, except in 

 the central portion of the Mississippi Basin now covers the country 

 south of Lat. 40 to the Gulf of Mexico. I may add here also 

 that one of the latest arrivals from Mexico, a Coleopteron Anthonomus 

 grandis, has apparently come through this gateway, and has now 

 pushed northward as far at least as San Antonio, Texas. In a paper 

 now in the hands of the Entomological Society of New York, awaiting 

 publication,* I have shown that our entire genus, Diabrotica, also 

 coleopterous, probably had its origin in Northern South America, a 

 number of our species having clearly pushed northward from Mexico. 

 So then the route laid down for the chinch bug is by no means a new 

 one. 



Finally I wish to call your attention to the fact that I did not 

 start out with the expectation of proving anything, except that Blissus 

 leucopterus did not necessarily, originate on the Atlantic coast of the 

 United States and move westward with the progress of grain growing. 

 I cannot claim strict originality, even, as I have used the suggestions 

 of Messrs. Schwarz and Marlatt as a nucleus about which to build. I 

 am simply the first to collect together all the available information, 

 giving my own translation of its meaning when thus brought together. 

 I cannot close without pointing out the rich field of research that lies 

 awaiting the investigator who chooses to take up the subject of the 

 northern spread of South and Central American Insects. 



It appears to me as though Mexico and Central America constitu- 

 ted a gigantic, biological cornucopia, that is continually pouring out its 

 wealth of species upon the country to the north. The outline of the 

 two countries does, somewhat, resemble a horn of plenty, and we cer- 

 tainly shall find that a considerable portion of our insect fauna has 

 been evolved from within their boundaries. The dividing line 



* Published in vol. iii., pp. 158-166, Journal of the New York Entomological 

 Society, 1895. 



