90 THE CHINCH BUG. 
time 1>\ Doctor Packard, on the summit, which has an elevation of 
6,500 feet. 
In his own experience, running over something like forty-live 
year-, the writer has never witnessed serious injury by chinch bugs 
to crop- on hilly land. It may be stated, however, that all of his 
studies of tie 1 insect have been carried on in a level country. Ohio 
being the most uneven and hilly, but even here all of the outbreaks 
observed were on level areas. In Minnesota, however. Doctor Lugger 
found that those grain field- which were most seriously injured 
were located near the edges of woods or on slopes. In some pub- 
lished observations of Professor Osborn, in Iowa, kindly placed 
at the writer'- disposal by Doctor Howard, we find that in 1894 about 
'.'<) per cent of the infested field- examined by Profe>>or Osborn were 
on high ground and about SO per cent of the fields were hilly and 
ridges, in most cases the damage being first apparent upon the 
higher portions of the fields. The exception- were where the chinch 
bug had evidently hibernated in wild grass and weeds occurring in 
the lower places, and these had been very dry for the twelve months 
preceding the damage of that year. Besides, both the Iowa and 
Minnesota areas are below 1.000 feet elevation. 
The area over which the chinch bug is more especially abundant 
and destructive comprises such a variety of soils and geological 
formations that a study of these factors at once shows that neither 
has any material influence in the distribution of the species, at least 
in the United States. In its northernmost habitat it would not be 
,;t all surprising that it should prefer a sandy, rather than a clay, 
soil, the former being looser and warmer on or near the surface. 
(See fig. 10.) 
In conclusion, then, on this point it may be stated that if Blissus 
leucopterus originated in the Western Hemisphere it was probably 
near the Tropics, and it i- not impossible that it- generic ancestors 
may have been carried from Europe or Africa by either the north 
equatorial or the main equatorial Atlantic currents, landing them 
on the northern shores of South America or on some closely located 
islands, from which the species ha- spread coastwise around the 
Caribbean Sea and the Gulf of Mexico, a- previously indicated. In 
thi- connection it is interesting to note that specimens from Grenada, 
collected on the Mount Joy and Caliveny estates by Mr. II. II. Smith 
in June and September, -how that the species here attain.- a large 
size and i- more variable, both in size and markings, than is com- 
monly found to be the case in the eastern United States. 
See paper by the writer on Origin and Diffusion of Blissus leucopterus and 
Murfjantia histrionica, in Journal of Cincinnati Society of Natural History. Vol. 
Will. February, L896. 
''I'liler on Hemiptera-Heteroptera from St. Vincent and Grenada. Proe. Zool. 
Soc, London, 1894. 
