OUR BIRDS FROM AN ECONOMIC STANDPOINT. 353 



were larvae, and you know that the larval life is the most destructive 

 period in an insect's life history. Of beetles, there was 21 per cent, 

 and 30 per cent of these were beetles which produce wire-worms ; 

 of Hcuiiptera, or bugs, there was 15 per cent; of Neiiroptera. 8 per 

 cent. Of crayfish there was 9 per cent : of vegetation i per cent. 

 Insufficient as the above date are for our purpose, the work was 

 most carefully performed. As an evidence of the labor required, this 

 scientist states that as much as a half a day was sometimes spent in 

 the examination of one stomach. It would seem, too, that the food 

 of nestlings is what we should study in this matter, for you know^ 

 the assiduity with which the parent birds bring food (consisting 

 of insects and insect larvae in the case of our common birds), to 

 their helpless young, and one important feature is to know what 

 proportion of injurious and neutral forms are found in this diet. 

 By neutral, is meant forms of insects which affect the farmer in no 

 known way either beneficially or injuriously. 



Then, too, the examination of stomachs of adult birds should 

 extend through a number of months and even through a number 

 of years, as influences which are absent one season may rnake them- 

 selves felt another season. 



Prof. S. A. Forbes, a scientist of high standing, publishes a re- 

 port of the robin, in a bulletin of the Illinois State Laboratory of 

 Natural History, based on the examination of 114 stomachs. Some 

 of the significant facts which he presents are the following : Insects 

 comprise 65 per cent of food for the whole year in 107 stomachs. 

 Of these 4 per cent from forty-one stomachs were Hymcnoptera; 

 in fifty-six stomachs there was 17 per cent of larvae of Lepidoptera. 

 Cutworms or cutworm moths 8 per cent for whole year in twenty- 

 three stomachs; beetles 18 per cent of year's food in eighty-one 

 stomachs, in which injurious forms were almost the entire repre- 

 sentation; thousand-legged worms were found in eight stomachs; 

 earth worms in one stomach ; blackberries 7 per cent of food for 

 year in twelve stomachs ; raspberries 2 per cent of year's food in 

 four stomachs; cherries 11 per cent of food in twenty-four stom- 

 achs ; curculio 2 per cent in six stomachs ; grapes 7 per cent in ten 

 stomachs ; mountain ash berries i per cent in two stomachs. The 

 birds upon which this work was done w^ere secured during the 

 months of February, ]\Iarch, April, IMay, June, July, August and 

 September. Summarizing he gave the following general ratios: 

 beneficial species, both vegetation and insects, found in the food of 

 the 114 birds, 36 per cent; injurious species, that is injurious insects 

 and seeds of weeds, 43 per cent ; neutral 21 per cent. 



