Eleventh Report op the State Entomologist 125 



was simple. With the removal of the bark, the decorticated portion — 

 not exceeding in many instances in thickness the diameter of a large 

 pin — dried, and becoming brittle, was readily broken off by a moderate 

 swaying of the wind. 



The girdhng of the twigs in this manner could serve the Orgyia no 

 such purpose as attends the girdling of several other insects, as the 

 Elaphidion pruners of oaks and maples, where it enables the insect to 

 attain greater security for its transformations through this method of reach- 

 ing the ground, or the (9«<r/V/i';wtwig-girdler,where the dead wood affords 

 suitable food for the larvae. Probably the conditions of growth during 

 the spring of this year were such as to render the young bark, at the point 

 attacked, particularly attractive to thelarvse; but why, after feeding upon 

 it to so limited an extent, it should cease and resume its feeding on the 

 leaves, cannot be explained. In a few instances where the twigs had 

 become detached quite near the node marking the commencement of the 

 year's growth, the bark had been irregularly eaten for an inch or more 

 in extent. 



While the Orgyia is a serious pest in Albany, it has its years of remark- 

 able abundance, and of comparative scarcity. Girdled tips, as above 

 described, have been seen each year since 1883, but by no means cor- 

 responding in number to the degree of abundance of the caterpillar. 

 My attention had not been drawn to them the present year, until much 

 later than the usual time — toward the end of August. At this time 

 (21st of August) many tips of unusual length and with perfectly fresh 

 leaves were collected from beneath a large American elm. Each one 

 had broken at the base of the girdling, which had probably been quite 

 near the node of the year's growth. They were of especial interest fi"om 

 their great length, varying from 10 to 18 inches. From the growth they 

 had attained, it was evident that the girdhng had not been done in the 

 spring or early summer, but in the late summer after the usual brood had 

 completed its transformations. It was clearly the work of a second brood 

 of the insect, and this was confirmed by my having seen a few days 

 previously from a house-top, while making observations on the elm-leaf 

 beetle, the Orgyia larva about one-half grown. 



A distinct second brood of the Orgyia has not been recorded in 

 Albany, although it is known to be double-brooded in Washington and 

 Philadelphia and probably in Brooklyn, and has also been observed in 

 Boston. The present year, however, has been an exceptional one in the 

 remarkable abundance, the rapid development and the injuriousness of 

 several of our more common insect pests. 



