42 THE BROAVN-TAn. MOTH. 



In the full the young larvjp feed upon the epidermis of 

 the leaves onh', causin^: them to turn as brown as though 

 scorched by fu-e, and Avhile still young commence the dwell- 

 ing in which they hibernate during the winter (Plate 8). 

 These winter webs of the brown-tail moth, constructed at 

 the ends of the twigs, are from one to four inches in length 

 and from one to one and one-half inches thick, depending 

 upon the kind of tree on which they occur (Plate (5, Fig. 2). 

 The insect readily adapts its style of architecture to the ma- 

 terial at hand, making compact webs on pear and willow, 

 and large open webs on maple and ash. Each web is com- 

 posed of a tenacious silken hibernaculum, enclosing leaves 

 from which the epidermis has been consumed, although the 

 outer leaves on the web may not have been attacked. The 

 webs are firml}^ attached to the twigs by stout bands of silk. 

 Almost invariabl}^ the web commences where the egg clus- 

 ter was deposited, and remains of it can usually be found 

 on or in each web. Exit holes sometimes remain open on 

 the webs throughout the winter, but as a rule they are closed 

 by the matting together of the web under the influence of 

 rain. The webs consist internally of numerous layers of 

 silk, enclosing a great many small, irregular, silk-lined 

 chambers, which are often connected, and coiit-.iin from six 

 to fifty larvie. The usual number found in the chambers is 

 about a dozen each. The larvje arc also often found in the 

 galleries in the web. The lowest part of the web is usually 

 full of fine black excrement, and the cast-off skins of the first 

 molt occur in many of the chambers. Twenty winter Avebs 

 of the l)i()\vn-tail moth wei'c opened Jan. 24, l8i)i>, and 

 their iiunates carefully counted, the webs being dissected 

 under a lens, so that none of the insects might be over- 

 looked. The webs contained respectively 253, 159, 253, 

 254, 223, mi, 182, li)3, 84, 89, 47, 93, 299, 380, G74, 

 2«1, (;(;4, (wl, «02 (the latter being a double web),— a 

 total of 5,804, uv an average of 290 eaterpillars per web. 



VV/e Larni. 

 The newly hatched larva is about one-twelfth of an inch 

 long, with a shining black head, over the surface of which 

 arc n few pule l)rownish-yellow barbed hairs. These hairs 



