152 The Food of Birds. 



find a spriiiklinii of ants (two per cent.), larvae of a Tene- 

 brionid {Mei'acantha contracta*) four per cent., and thou- 

 sand-legs (lulida?) one per cent. Long strips of grass, in 

 pieces much too large to have been eaten by any of the in- 

 sects present, were found in the stomachs of two of these 

 birds, and also occurred during each of the three following 

 months. I am in doubt whether these were taken as food ; 

 but, since I have found them in no other bird, and since 

 a species which feeds so largely on cutworms and grass- 

 hoppers may have acquired the power of digesting the 

 very considerable quantities of grass contained in the in- 

 testines of these insects, I have thought it best to include 

 them in the percentages of food. It is probable, however, 

 that they were swallowed accidentally with insects taken 

 from the ground. 



It will be noticed that the excess of Coleoptera in April 

 is largely compensated by the diminished quantities of 

 Orthoptera and caterpillars. 



Ma y . 



In this month nine birds were taken, from six localities 

 in central and northern Illinois, in 1876-80. The Lepi- 

 doptera, Coleoptera and Orthoptera return to about their 

 normal ratios, but spiders rise to the excessive figure of 

 twenty-one per cent. This ratio is, however, partly mis. 

 leading, as, although six of the nine birds had eaten spi- 

 ders, yet eleven per cent, is due to a single bird, which had 

 eaten nothing else. In such a case a larger number of 

 specimens is required to restore the balance, so violently 

 disturbed. Two birds of this month had eaten moths, and 

 five had eaten cutworms. The averages stand fifty-five 

 per cent, of moths, caterpillars, June-beetles, curculiosand 

 Orthoptera, opposed to thirty-five per cent, of Carabidas, 

 soldier-bugs and spiders. The Oarabidfe include Cratacan- 

 thus dubius^ Agonoderus comma^ Anisodactylus, and Har- 

 palus. Other details may be obtained from the table at 

 the close of this paper. 



*For the determination of this species and most of the other larvae 

 which have been identified specifically, I am under obligations to Pro- 

 fessor Riley. 



