143 ILLINOIS ACADEMY OF SCIENCE. 



entomological collections who may have ant material they would 

 like to have identified. If so, I should be very glad to determine 

 the material for them for the sake of getting data on the occur- 

 rence and distribution of the various species in the state. With 

 such help and with the opportunity which Professor Forbes has 

 allowed me of working over the large amount of as yet undeter- 

 mined material of the State Laboratory, I hope some time in the 

 future to be able to publish a complete annotated list of the ants 

 of the state. 



In building up my own collection I am indebted to a number of 

 friends and co-workers, but especially to Messrs. W. P. Flint and 

 G. E. Sanders, assistants to the State Entomologist. I am also 

 indebted to Prof. S. A. Forbes for permission to use the extensive 

 collections of the State Laboratory, and to Prof. W. M. Wheeler 

 for making many determinations for me and for adding materially 

 to my list. 



THE MOLLUSCA OF PIATT, CHAMPAIGN AND VER- 

 MILION COUNTIES, ILLINOIS. 

 By James Zetek, 

 Illinois State Laboratory of Natural History, Urbana. 

 (Abstract.) 



The paper records the result of a molluscan reconnoissance of 

 Piatt, Champaign and Vermilion counties. Previous to 1907 but 

 twenty-eight species had been recorded from this area. The 

 work of the past four years has raised this number to 116, dis- 

 tributed as follows : Piatt county, 53 ; Champaign county, 78 ; 

 Vermilion county, 67; total 116. Of this number, 44 are pelecy- 

 pods, 9 are prosobranchiate gastropods, 30 are aquatic pulmonata, 

 and 43 are terrestrial pulmonata. 



Fourteen different localities were visited and more or less 

 extensive ecological observations were made ; ten of these locali- 

 ties were in Champaign County, and two each in Piatt and Ver- 

 milion counties. Of the localities visited only two, the Brown- 

 field and Cottonwood groves, three and one-quarter and four 

 miles northeast of Urbana, were systematically searched for mol- 

 lusks. It is believed that an equally careful study of the other 

 localities will materially add to the number of species herein re- 

 corded. 



The finding of Paravitrea significans (Bid.) in the Brownfield 

 and Cottonwood groves is of great interest, extending the range 

 of this species 300 miles northward. 



