43 



Pliyllopliaga balia Say 



We obtained but eight specimens of balia, all from the northern 

 and central sections of the state at various dates between April 28 and 

 June 8. They were from birch, hazel, apple, and gooseberry, but in 

 numbers too small to give any definite indication of the food of the 

 species. 



Pliyllopliaga bar da Horn 



Our 5 specimens of barda, obtained from April 25 to May 26, 

 1908, at Danville, Carbondale, and Anna, in central and southern 

 Illinois, were all from lights. 



Pliyllopliaga calceata Horn 



Calceata was obtained by us only in 1907, 2 specimens from the 

 central part of the state and 8 from the southern part, May 22 to 

 June 27, all at lights. 



Pliyllopliaga Jiirtiventris Horn 



Hirtiventris is represented by but 2 specimens from Metropolis, 

 on the Ohio River. They were obtained from lights June 22, 1908. 



The foregoing accounts for all our collections of the years men- 

 tioned, except some twenty specimens not yet satisfactorily determined. 



The Species by Sections of the State 



Northern Illinois Species. — In northern Illinois there were but 

 three species, rugosa, anxia, and nitida, so far limited to that section 

 that they may properly be called northern species. Rugosa yielded 

 us from northern Illinois 2326 specimens out of 15,457 of all species 

 collected there, 410 specimens out of 78,916 from central Illinois, and 

 33 out of 20,120 from southern Illinois — numbers equivalent to 15 

 percent, .52 of 1 percent, and .16 of 1 percent from the three sections, 

 respectively. As a poplar-willow species its ecological affiliations lie 

 northward rather than southward, but its food-plants are common 

 enough, at least along watercourses, in central and southern Illinois 

 to permit its extension into those areas. Anxia, a May-beetle of di- 

 versified food habits, distinguished by its preference for elm but other- 

 wise mainly a willow-poplar species, occurs thruout the state, but it 

 gives from northern Illinois a percentage of specimens a hundred and 

 twenty-seven times as large as that from central Illinois and over 

 forty times as large as that from southern Illinois ; that is, our north- 

 ern Illinois collections of anxia were 12.7 percent of the total number 

 of May-beetles there, and the corresponding ratios for the other two 

 sections were .1 of 1 percent for the central and .37 of 1 percent for 



