THE STATE ENTOMOLO&IST. 119 



them to feed ui on, but they are so tough and hardy that they cau. 

 fast for many days with impunity, and the glutinous substance on 

 the outside of their eggs furnishes good sustenance and gives them 

 strength at first. It is even asserted by Mr. H. C. Raymond, of Coun- 

 cil Bluffs, Iowa, that the eggs often hatch in the fall and that in these 

 cases the larva? withstand the severity of the winter with impunity. 

 The young caterpillars commence spinning the moment they are 

 born, and indeed they never move without extending their thread 

 wherever they go. All the individuals hatched from the same batch 

 of eggs work together in harmony, and each performs its share of 

 building the common tent, under which they shelter when not feed- 

 ing and during inclement weather. They usually feed twice each 

 day, namely, once in the forenoon and once in the afternoon. After 

 feeding for five or six weeks, during which time they change 

 their skins four times, these caterpillars acquire their full growth, 

 when they appear as at Figure 50 (a side view, I back view) the col- 

 ors being black, white, blue and rufous or reddish. They then scat- 

 ter in all directions in search of some cozy and sheltered nook, such 

 as the crevice or angle of a fence, and having finally decided on the 

 spot, each one spins an oblong-oval yellow cocoon (Fig. 50, d) the silk 

 composing which is intermixed with a yellow fluid or paste, which 

 dries into a powder looking something like sulphur. A few individ- 

 uals almost always remain and spin up in the tent, and these co- 

 coons will be found intermixed with the black excrement long after 

 the old tent is deserted. 



Within this cocoon the caterpillar soon assumes the chrysalis 

 J7>s, 51^ state, and from it, at the end of about 



[three weeks, the perfect insect issues as 

 a dull yellowish-brown or reddish-brown 

 moth (Fig. 51), characterized chiefly by 

 the front wings being divided into three 

 W nearly equal parts by two transverse 



whitish, or pale yellowish lines, and by the middle space between 

 these lines being paler than in the rest of the wing in the males, 

 though it is more often of the same color, or even darker in the fe- 

 males. The species is, however, very variable.* 



The moths do not feed, and the sole aim of their lives seems to be 

 the perpetuation of their kind; for as soon as they have paired and 

 each female has carefully consigned her eggs to some twig, they die, 



* Dr. Fitch, in the very excellent and detailed account of this insect in his second Report, 

 shows how very variable the moth is, and from a large series of bred and captured specimens, I 

 can fully corroborate the fact. I have specimens which are of an almost uniform pale tawny-yel- 

 low, while others are very dark, being what might be termed a bay-brown with the pale markings 

 conspicuous, while others have a pale band across the hind wings so conspicuous as to very closely 

 resemble the European neustria. Dr. Fitch in referring to his figures must certainly have made a 

 mistake, for he calls Figure 4 the female and Figure 3 the male, wlnle the reverse is apparent front 

 the fio-ures themselves. My own figure is intended to represent the female, but the middle space of 

 the upper wings seldom if ever appears so light in this sex, as the engraver has erroneously repre- 

 sented. 



