84 Indian Museum Notes. [Vol. IV. 



It appears from this table that the average quantity of insect 

 material in these gcg stomachs was almost 24 per cent. A moment's 

 examination of the table shows, however, that the number of stomachs 

 examined in different months is very unequal, and also that the per- 

 centage varies widely according to season. The average percentage 

 represents the proportion of insects to the whole stomach contents? 

 but from 7 to 10 per cent, of the stomach contents is sand or gravel. 

 Throwing out this mineral element, it appears that on the average, 

 26*17 per cent, of the Crow's food for the year is made up of insects. 

 In the same way it is found that even in January, when the smallest 

 proportion is eaten, insects form almost 3 per cent {2"]\) of the food, 

 while the maximum is reached in April with almost 53 per cent. 

 (52'75). In May, insects constitute about 49 per cent. (48'97) of the 

 food, and in June about 41 1 per cent. 



During the months of May and June 529 stomachs were collected, 

 insects formed 46'7 per cent, of all food in these stomachs. Since 

 these two months cover the larger part of the time when Crows are 

 rearing young, this large proportion of insect food perhaps is not 

 surprising, especially as 396 stomachs were those of young Crows 

 taken from the nest. The insect food in the stomachs of these nest- 

 lings averaged 49'6 per cent., while the average amount in the 

 stomachs of 120 adult Crows taken during May and June was only 

 36*4 per cent. This shows conclusively that young Crows while in 

 the nest eat more insects than the adults, the difference in this case 

 amounting to more than 13 per cent, of the entire fcod ; or to put the 

 matter in another form, nestling Crows eat at least one-third more 

 insects than the adults. It is of great importance, however, that the 

 character of this insect food be carefully determined, so that we may 

 know positively whether its consumption is or is not of benefit to the 

 agriculturist. Fortunately, this has been done. After the prelimi- 

 nary examination of the contents of each stomach and the determi- 

 nation of the percentages of the several kinds of food contained the 

 insect material was referred to Professor C. V. Riley, then Chief of 

 the Division of Entomology, under whose direction it was thoroughly 

 studied by Mr. E. A. Schwarz. The following reports contain the 

 results of this examination : — 



Report on the insect food of the crow. By E. A. Schwarz^ Assistant, 

 Division of Entomology. 

 The examination of the contents of about 600 stomachs of Crows^ 



• The insect contents of 8oi Crow stomachs were submitted to Professor Riley for 

 examination, but in several cases where many stomachs were collected on the same day and 

 at the same place, under precisely similar circumstances, it was not thought necessary that all 

 should be examined critically. In such cases half or more were thoroughly examined and the 

 lesults tabulated, while the remainder were passed over with a simple inspection.— W. B. B. 



