Article VTI. — On I In- IlidhKjti nf the Sand J/v-r/.s of I///iiois. 

 By Charles A. Hart and Henry Allan Gleason. 



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, Imt no systematic study of eitherwas attempted 

 until August. IDIlo. when a brief survey was made of this local- 

 ity and of similar regions southeast and south of Havana in 

 company with Mi-. H. A. (ileason, 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 remai'kable barren area called the Devil's Neck. 

 The botanical results of these two trips are presented by 

 Ml". 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 l)rief visit June 23 to the Illinois varlley 

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

 a few days studying the sandy reaches on the flats liordering 

 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 availal)le for these visits enabled me 

 merely to secure .some knowledge of the al)undaut, varied, and 

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

 highly interesting biological problems for future inve.stigatiou. 



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