342 Illinois State Lithorafonj of Xafurdl Hi.iforij. 



The species is one of the most abundant members of the 

 family in all parts of Illinois. Specimens are in the collection 

 of this Laboratory from Geneva, Cedar Lake, Colona, Geneseo, 

 Peoria, Pekin, Normal, Urbana, Warsaw, Union county, and 

 Cairo. 



Size and color are extremely variable. In most specimens 

 from central and northern Illinois the markings are all very 

 obscure, and often the triangular spot between the eyes is so 

 indistinct as to require close looking to detect it. Others of the 

 marks described above may even be wanting, and in but few 

 specimens are all the marks plainly visible. The greenish and 

 reddish forms seem to be more abundant in southern Illinois. 

 The skin of the more northern individuals is rougher, the 

 warts often being elongate and ranged so as to form short 

 ridges. 



This is a rather coarsely built frog, bearing a close resem- 

 blance in build to the Ranidje. It is more strictly terrestrial 

 than our other Hylidii3, and. probably never resorts to shrubs 

 and trees. It is usually found at the margins of streams or 

 pools, into which it leaps when disturbed, but only to return to 

 the shore a short distance from the observer. It is a good 

 swimmer, as its webbed hind feet indicate. Its note is a rap- 

 idly repeated grating noise, thought to resemble the trilling of 

 a cricket, whence the name cricket-frog. Its food consists of 

 insects, and if the habits of the frogs led them more frequently 

 into cultivated grounds they would doubtless do good service 

 to agriculture in destroying aphides. Among other insects, 

 Chlorops, crane flies, Thyreocoris, Calocoris rapidus^ numer- 

 ous pupiL' and wingless female Aphididii' and ()rth()i)tera, have 

 been determined from the contents of their stomachs. Exam- 

 ples nearly grown were taken November 17, 1SS8, under logs 

 in the vicinity of a creek in ('hampaign county, where they 

 were hibernating. 



The variety (/rij//iis of this spei-ies has been credited to 

 Illinois and prubal^ly occurs about the shallow lakes of the 

 south part of the State. LeConte's characterization of the 

 two forms in the Proceedings of the Philadelphia Academy is 

 the best extant, but the only difference he presents which in 

 so variable a species is of varietal importance, is the size (l.l 



