Report of tee State Entomologist 227 



one-half in length. ItB black body is thickly covered with long, stiff, 



barbed, spine-like hairs, which are of even length like close-cut 



bristles of a brush. The first four segments (of the twelve in which 



the body of caterpillars are divided) are black, as are also the last two, 



while the intermediate ones are red or chestnut-brown. If taken in 



the hand or arrested in its joumeyings with a stick or the foot, in 



rolls itself up in a ring, almost as tightly as the armadillo is reported 



to do, and for the same purpose — to protect itself from harm, or 



possible only as an inherited instinctive act. From this habit it 



has been given the name by which it is known in some of the 



western states, of "the hedge-hog caterpillar." It is represented in 



Fig. 1, at a. 



Transformations of the Insect. 



At this season of the year (autumn) the caterpillar is not fully 

 matured. It therefore retires, upon the approach of freezing weather, 

 to some concealed place, as in an old stone wall, within a wood-pile, or 

 under a board, where, rolled in a ring or doubled up like a bear, it 

 may pass the winter in a semi-torpid state. Here it remains, unless a 

 succession of warm days should draw it temporarily from its retreat, 

 until the warmth of spring arouses it again into activity. 



It comes abroad and feeds for a while on almost any garden or other 

 succulent plant that it finds conveniently at hand. It is soon full-fed 

 and in readiness in April or May for its transformations.* Again it 

 retires to shelter, when it incloses itself within a dark-colored oval 

 cocoon, consisting of a silken thread that it spins into a firm web 

 about it, interwoven with the hairs rubbed or plucked from its body. 

 The cocoon torn open, showing the pupa within, is represented in the 

 above figure, at 6. 



Within the cocoon it throws off its caterpillar skin and becomes a 

 shining black, blunt-ended pupa. When ready for its final change 

 the pupal case is rent by the movements of the imprisoned insect, 

 and the moth emerges. Within a half-hour, with expanded and dried 

 wings, it has become a perfect creature, prepared for flight, and for 

 seeking the companionship of its mate. This last stage usually occurs 

 during the months of June or July. 



The Moth Described. 

 The moth is not conspicuous in coloring. Its wings are dull yel- 

 low or a yellow-buff, with a few black dots and two or three indistinct 

 brownish lines crossing the outer half of the front pair. The hinder 



[♦ Mr. H. G. Dyar reports, as the result of his observations upon this Insect, that the 

 larva undergoes nine moltings before pupation— the larsrest number In twenty-eight 

 species of Bombycidce of which he has recorded the stages— five being the usual 

 number.] 



