40 



moth just described, it is covered, though rather less completely, 

 with tufts of hair of different color ; some tufts being cream color, 

 others black, others yellow. The head is bright red. The gene- 

 ral color of the body is yellow. The thick, short tufts of hair seen 

 on the back are yellow or cream color, the long tufts are black 

 and the side tufts are yellow. They usually feed in company 

 and infest various trees ; sometimes they are very common on 

 the apple, sometimes on the elm, sometimes on other trees or 

 shrubs. It seems to vary its habits more than most insects 

 do, for although usually a leaf eater it sometimes eats into young 

 apples, and Dr. Lintner gives an account of a very singular 

 variation in habit which occurred in Albany some few years ago. 

 It also varies greatly in abundance, one year being very common 

 and injurious, and then for a year or several years being quite un- 

 common. In the instance just named, the Orgyias, which had 

 previously attacked the leaves, left these and began to girdle the 

 young growing twigs too ; so completely did they accomplish this 

 that great numbers perished and were broken oft' by the wind, so 

 that the walks weie thickly strewed with them. Figure 30, copied 

 from Dr. Lintner's Report, shows how the twigs were eaten. It is 

 remarkable that only elms were girdled in this way. Neighboring 

 trees subject to the ordinary attacks of the insects, such as maples 

 and horse chestnuts, were untouched. Dr. Lintner thinks that the 

 Orgyias were unusually numerous because of the English sparrow. 

 This bird does not at all molest these insects, but does drive oft' 

 other birds that would devour it. In regard to this Dr. Lintner 

 says, in his second Report as Entomologist of New York: "On 

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

 standing between two maples showed every leaf eaten from them, 

 disclosing the nesting boxes among their branches and their trunks 

 and limbs dotted thickly, or clustered with the easily recognized 

 egg-bearing cocoons of Orgy ia. Hundreds of immature caterpill- 

 ars were creeping over the trees, fences and walks adjoining," and 

 this in spite of the fact that the nesting boxes named were occupi- 

 ed by English sparrows. After feeding for about a month the 

 larvae spin cocoons, which they attach to some part of the trees or 

 in places not far away. In from ten days to two weeks the moths 

 emerge. The males and females are very unlike, as figures 31 



