BIRDS IN RELATION TO THE ALFALFA WEEVIL. 



51 



progressed probably would be manifest. The largest amount eaten 

 by any was by a nestling 3 or 4 days old, which had 13 larvae and 

 14 adults in its stomach. Orthoptera (grasshoppers and crickets) 

 continued to increase and in this series of stomachs comprised nearly 

 a quarter (24.71 per cent) of the total contents, being eaten by 20 

 of the 35 birds. Ground beetles, Hemiptera, Lepidoptera, and 

 Hymenoptera, made up the bulk of the remainder. The vegetable 

 food, practically all grain, amounted to 58.20 per cent. 



MAY 1-15 



MAY 16-31 



JUNE 1-15 



JUNE 16-30 



JULY 1-15 

 EXPLANATION 



JULY 16-31 



.■■...■■ 



CA TFft&LLA&S 



<S/B^//V 



M/SC£lLAA/£Dl/S 



Fig. 2. — Diagram showing the food of young English sparrows during semimonthly periods 



in May, June, and July. 



The diagram presented in figure 2 and the following tabulation 

 represent each of the six semimonthly periods from the first of May 

 to the end of July, and the proportions of the various food elements 

 may easily be seen by comparing the various sectors of the different 

 circles : 



Semimonthly periods. 



Alfalfa 



Grass- 



Caterpil- 



Grain. 



weevils. 



hoppers. 



lars. 



14.00 



0.94 



4.19 



65.62 



36.12 



.66 



18. 36 



25.05 



26.75 



1.03 



11.30 



38.84 



18.25 



16.30 



19.64 



36.64 



.77 



35.23 



8.82 



51.83 



9.20 



24.71 



1.86 



58.20 



Miscella- 

 neous. 



May 1-15. 

 May 16-31. 

 June 1-15. 

 June 16-30 

 July 1-15.. 

 July 16-31. 



15.25 

 19.81 

 22.08 

 9.17 

 3.35 

 6.03 



