FOOD OP ROBINS AND BLUEBIRDS. 21 



Diptera (flies), like Hymenoptera, are quick of wing and not easily 

 taken either in midair or sitting; consequently they, too, enter 

 lightly into the diet of the bluebird, the total for the year being 

 only 0.26 per cent; they do not amount to 1 per cent in any month 

 and are entirely missing in four. Hemiptera (bugs) are eaten in 

 moderation every month. In July they amount to 6.49 per cent and 

 in March 6.01 per cent, the highest two points of the year. The 

 average for the 12 months is only 2.75. While a number of families 

 were represented, the Pentatomidae, or stinkbugs, predominated. 

 Remains of chinch bugs (Blissus leucopterus) were found in one 

 stomach. 



Lepidoptera (caterpillars, with a few moths) form an important 

 and regular article of food of the bluebird. The greatest consump- 

 tion, 18.82 per cent, occurs in March, and the least, 4.58 per cent, in 

 December. Most of these insects were of the family Noctuidae or 

 owlet moths whose larvae are the well known cutworms, though a 

 few belonged to the Arctiidse of which the larvae are hairy cater- 

 pillars. One of these, Spilosoma virginica, the yellow bear, was 

 identified in three stomachs. The average consumption for the year 

 is 10.48 per cent, the third greatest article of animal food. 



Orthoptera (grasshoppers, crickets, and katydids) furnish the 

 largest item of animal food, amounting to a good percentage in 

 every month, and in August and September aggregating 52.68 and 

 53.47 per cent, respectively. The month of least consumption is 

 January, when they amount to 5.98 per cent, and the average for 

 the whole year is 22.01 per cent. The number eaten in each month 

 is about proportionate to their abundance. Orthoptera are evidently 

 a preferred food and sought for at all times. They were found in 423 

 stomachs and were the sole contents of»19. In only four months does 

 the quantity eaten fall below 15 per cent of the whole food. Most 

 insects of this order are harmful and when abundant are very destruc- 

 tive. Fortunately most birds are fond of these insects and eat them 

 freety whenever obtainable, and some species not at other times 

 remarkably insectivorous eat grasshoppers when they are super- 

 abundant. 



A few insects of other orders were eaten very 'irregularly and 

 amount to only 0.34 per cent of the food. Spiders, more relished by 

 the bluebird than by the robin, constitute a fairly large percentage 

 of the food from March to July, but are taken to some extent every 

 month ; the average for the whole year is 4.37 per cent. Myriapods 

 (thousand-legs), which seem to be eaten whenever they appear in 

 the open, were contained in small quantities in the stomachs taken 

 in every month but two. The average for the year was 1.20 per 

 cent. The remainder of the animal food (0.57 per cent) consisted 



