THE SPARROW THE CAUSE OF THE ORGYIA INCREASE. 8l 



established themselves, their little flocks are continually before the eye, 

 and their unceasing chatter constantly in the ear, almost to the exclu- 

 sion of other sounds. 



The increase of the Orgyia leucostigma commenced and has contin- 

 tinued to progress with that of the sparrow. 



A remark made to me that the caterpillars had been observed to be 

 very numerous in localities where the sparrows also abounded, induced 

 me to undertake to verify or disprove the idea that had suggested itself 

 to me, that the sparrow afforded actual protection to the caterpillars, 

 and promoted their increase. 



In a locality in the city (intersectionof Broadway and Spencer streets), 

 which I had traversed daily during the preceding year, I had been inter- 

 ested in watching the habits of a large company of sparrows which had 

 established themselves in quarters evidently in every way suited to their 

 taste and wants, among the vines and leaves of a large woodbine 

 {Ampelopsis qiiinquefolia) which covered with a dense matting nearly 

 the entire side of a large dwelling. Here I had observed a greater 

 number of the sparrows than elsewhere in the city: they were still local, 

 and far from being generally distributed. 



Upon visiting this locality for the purpose above mentioned, I found 

 upon the other side of the building and on an adjoining one, three 

 other large woodbines not before noticed by me — making five in all. 

 On a tall pole standing between the two buildings, a very large sparrow 

 house, with many compartments, had been erected, and many smaller 

 ones had been placed among the branches of the trees. The wood- 

 bines seemed alive with the sparrows : hundreds were issuing from them 

 and dropping down to their favorite stercoraceous repasts in the streets, 

 and the air was vocal with their chattering. It was a rare bird-exhibi- 

 tion. Here certainly was a test-case of the " insectivorous nature " of 

 the sparrow. 



On the sidewalk in front of the two buildings, two large, spreading 

 elms ( Uhmis Aniericanus) standing between some maples, showed every 

 leaf eaten from them, d\?,c\os\ng the nesting-boxes among their branches, 

 and their trunks and limbs dotted thickly, or clustered with the easily- 

 recognized egg-bearing cocoons of the Orgyia. Hundreds of imma- 

 ture caterpillars were traveling over the trees, fences, and the walls ad- 

 joining. No better evidence of the almost perfect immunity afforded 

 to the caterpillars from their enemies — whether birds or insects — by 

 the presence of the sparrows, could possibly be given. 



A portion of Broadway, between Clinton avenue and the Central 

 railroad crossing, was also known to abound in the sparrows, the citizens 

 11 



