OBSERVATIONS ON BIRDS. 



209 



the fact that the body of the caterpillar is covered with small 

 hairs, which become detached, and, piercing somewhat the 

 skin of persons and animals, cause great itching.* 



I have found very little evidence in the writings of Euro- 

 pean authors that birds other than the cuckoo and the tit- 

 mice destroy the larvae of the gypsy moth, although several 

 species are said to destroy the eggs.j In this country, how- 

 ever, the reverse appears to be true. Few birds seem to 

 eat the eggs, while many attack all other forms of the moth. 

 In the season of 1891 my attention was first called to the fact 

 that certain birds were devouring large numbers of the larvae. 

 The accuracy of the reports received was soon verified by 

 my own observations. Several species of birds were seen 

 busily engaged in eating the insects wherever they were 

 numerous. The inspectors were directed to record all 

 observations made on birds which were feeding on the cater- 

 pillars. 



Unfortunately, there were at that time only eleven observ- 

 ers on the force who could accurately identify birds in the 

 field. These men were also perfectly familiar with the dif- 

 ferent forms of the moth. The notes made by them indi- 

 cated that thirteen species of birds were feeding on the 

 moth in one or more of its forms. The observations begun 

 in 1891 have been continued during a part of each succeed- 

 ing summer. Although as a rule they have been made inci- 

 dentally in connection with the work in the field, one or 

 more men have been detailed at times to disprove or confirm 

 reports that have been made, or to watch some particular 

 species of bird, so that some points in regard to its value as 

 a moth destroyer might be settled. Where the caterpillars 

 are very numerous, they cluster in masses on trees. Cer- 

 tain birds habitually visit these swarms either to eat the 

 caterpillars or to take them as food to their young. If the 

 observer remained quietly at his post, he was able to view 

 them at a distance of a few feet or yards. Each observer was 



* Translated from "Injurious Insects" by Theodore Keppen, 3d Vol., special 

 part. 



t In a recent letter Dr. Ebermayer of Munich names starlings, crows, titmice and 

 tree creepers among the enemies of the gypsy moth but does not say what form of 

 the moth they destroy. 



