60 BULLETIN 621, U. S. DEPARTMENT OF AGRICULTURE. 



crow, young or old. Four partly feathered young, also from Kansas, 

 had devoured 259 grasshoppers; another brood of four made away 

 with 222 ; and a series of nine, made up of probably two broods, 

 averaged 50 apiece. Seven other individual nestlings had eaten 50 

 or more ; 31 had taken from 25 to 49 ; and 44, 10 to 24 apiece. Fre- 

 quently grasshoppers were associated with locustid or cricket remains, 

 the combined bulk often forming the major portion of the food. In 

 one stomach orthopterous insects formed the entire contents, in 35 

 they constituted from 75 to 99 per cent, and in 49 others they com- 

 posed from 50 to 74 per cent. 



Two series of young crows from Onaga, Kans., one of 157 taken in 

 1913 and another of 164 secured in 1914, revealed interesting data 

 regarding the relation of these birds to grasshoppers in years when 

 the insects are abundant. In working up this material, it was noticed 

 that in the former year grasshoppers were by far the most important 

 item of the diet, forming 42 per cent of the food and occurring in 

 151 of the 157 stomachs. In 1914 these insects constituted less than 

 12 per cent of the food and were present in 123 of the 164 stomachs, 

 in many of which merely a "trace" was recorded. It was in the 

 material taken in 1913 also that all the phenomenal records men- 

 tioned above were noted. In 1914, only 7 of the entire lot of 

 young crows examined subsisted on grasshoppers to the extent of 

 more than half their diet. Facts which can be correlated with this 

 wide difference in the food of crows in the same locality in two suc- 

 cessive years have been obtained from W. It. Walton, of the Bureau 

 of Entomology, who has stated that, although 1913 was not a year 

 of extraordinary abundance of grasshoppers in Kansas, 1914 was a 

 season of uncommon scarcity, especially in spring and early summer. 

 Exceedingly heavy rainfall is the reason assigned for lack of normal 

 numbers. The importance of young crows as a factor in grasshopper 

 control during an outbreak of the insects is a matter of interesting 

 conjecture. 



Lepidoptera. 



Caterpillars occurred in more than a third of the stomachs of 

 nestling crows and formed 5.34 per cent of their food. These soft, 

 easily digested larvae are among the first items fed to newly hatched 

 young, but as the birds grow older other insect forms soon displace 

 them in the diet. Birds which had been fed most extensively on 

 them were, as a rule, less than 4 days old. A brood of four, 1 to 2 

 days old, collected at Onaga, Kans., had eaten over 300. Two of 

 another brood, 3 days old, taken at the same place, had devoured 115 

 and 109, respectively. One partly feathered nestling had been fed 

 over 100, and another 92. Large numbers also were found in each of 



