FIELD STARRuW. 
79 
The laboratory investigation includes 175 stomachs, collected daring 
every month of the year, from 15 States and the District of Columbia. 
chiefly in New York. Massachusetts, and the District of Columbia in 
the East, and Kansas and Wyoming in the West. Of the total food 
they contained 41 percent was animal matter and 59 percent vegetable 
matter. Of the animal material weevils form 2 percent; leaf-beetles, 
2 percent: ground-, tiger-, click-, and May-beetles, collectively, 9 
percent; caterpillars. 4 percent; grasshoppers. 6 percent : leaf-hoppers, 
true bugs, sawflies, ants, flies, and spiders, taken together, 14 percent, 
and parasitic wasps. 4 percent. This last item is the principal point 
wherein the field sparrow differs in food habits from the chipping 
Fig. 16.— Field sparrow. 
sparrow — a difference that is not to the advantage of the record of the 
species from an economic standpoint, since, as has been shown, these 
wasps are dangerous parasites of many caterpillars. Of the vegetable 
food 51 percent consists of the seed of grasses, tor the most part such 
species as crab-grass and other panicums. pigeon-grass, broom sedge, 
poverty grass (Aristida), and sheathed rush grass. Seeds of such 
weeds as chickweed, lamb's-quarters, gromwell. amaranth, purslane, 
spurge, wood sorrel, and knotweed amount to 4 percent. The per- 
centage of timothy is insignificant, but that of oats is comparatively 
large, as they constitute 4 percent of the food. 
