Article VII.— -On the Biology of the Sand Amis of Illinois. 

 By Charles A. Hart and Henry Allan (Ileason. 



Introduction. 

 While located at Havana in connection with the work of 

 the Illinois Biological Station on the Illinois River, the writer 

 made a few trips to the tract of waste sandy land lying east of 

 the city, locally known as the Devil's Hole. A novel fauna and 

 flora were noted, but no systematic study of either was attempted 

 until August, 1903, when a brief survey was made of this local- 

 ity and of similar regions southeast and south of Havana in 

 company with Mr. H. A. Gleason, of the Department of Botany 

 at the University of Illinois, who studied the flora, the writer 

 giving attention to the fauna, especially to the insect life. At 

 the same season in the following, year we made a second visit 

 to these regions, and also examined the sandy tract lying north- 

 east of Havana, between that city and Pekin, which culmi- 

 nates in a remarkable barren area called the Devil's Neck. 

 The botanical results of these two trips are presented by 

 Mr. Gleason as the second part of this joint article. In 1905 

 I was enabled to make brief comparative examinations of these 

 same regions in the early part of the season, and of similar sand 

 areas in other parts of western Illinois in August and Septem- 

 ber. In 1906 I paid a brief visit June 23 to the Illinois valley 

 sand region, stopping off at Bishop, 111.; and in August spent 

 a few days studying the sandy reaches on the flats bordering 

 Lake Michigan above Waukegan, 111. Delays in going to press 

 have enabled me to include herein some important data from 

 the latter locality concerning species already on the list. The 

 limited amount of time available for these visits enabled me 

 merely to secure some knowledge of the abundant, varied, and 

 largely unfamiliar insect fauna, and to develop a large crop of 

 highly interesting biological problems for future investigation. 



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