185 



The Life Zones of Indiana as Illustrated by the Distri- 

 bution of Orthoptera and Coleoptera 

 Within the State. 



By W. S. Blatchley. 



During the past twenty years much of my spare time has been de- 

 voted to the collecting and classification of the insects of Indiana, es- 

 pecially Orthoptera, or katydids and grasshoppers, and Coleoptera, or 

 beetles. In the report of the Department of Geology for 1902 the results 

 of the work on Orthoptera were published, about 150 species being therein 

 classified and described. The Coleoptera are at present being worked up, 

 and I hope to be able to publish a descriptive catalogue of them within 

 the next two years. Up to the present about 2,700 species have been col- 

 lected in the State. 



The collecting and detailed study of the distribution of the above men- 

 tioned insects in Indiana has developed certain facts regarding the life 

 zones of the State which I thought might be of interest. In a map ac- 

 companying his paper entitled "Life Zones and Crop Zones of the United 

 States," published in 1898, Dr. C H. Merriam, chief of the Biological Sur- 

 vey of the U. S. Department of Agriculture, showed the "Upper Austral 

 Zone" as covering the entire State with the exception of a very small 

 area of the Lower Austral in the extreme southwestern corner. The facts 

 brought out regarding the distribution of Orthoptera and Coleoptera in 

 Indiana, which are supplemented by numerous field notes on other groups 

 of insect and animal life, and on the flowering plants, prove conclusively 

 that the "Transition Zone," represented by the Alleghanian fauna and 

 flora, overlaps the northern fourth of the State, while the "Lower Austral 

 Zone," represented by the Austroriparian fauna and flora, overlaps the 

 greater part of the southern third. The Carolinian fauna and flora of the 

 Upper Austral embraces, of course, the prevailing forms of life in the 

 State, 93 of the 118 species of Orthoptera belonging to it. The majority 

 of these range over the entire State, mingling with the representatives of 

 the Alleghanian fauna in the north and with those of the Austroriparian 

 fauna in the southern third. The proportion of Coleoptera belonging to 



