THE STATE ENTOMOLOGIST. 75 



though I have found full grown specimens that were equally as 

 green as the younger ones, they more generally assume a pale straw 

 or reddish-brown color, and the long recurved horn is invariably 

 replaced by a highly polished lenticular tubercle. The descriptions 

 extant of this worm are quite brief and incomplete. The specimen 

 from which my drawing was made, was of a pale straw color which 

 deepened at the sides and finally merged into a rich vandyke-brown. 

 A line of a feuille-morie brown, deep and distinct on the anterior 

 part, but indistinct and almost effaced on the posterior part of each 

 segment, ran along the back, and another line of the same color, con- 

 tinuous, and with its upper edge fading gradually, extended along 

 each side. The six scalloped spots were cream-colored ; the head, 

 thoracic segments and breathing-holes inclined to flesh-color, and the 

 prolegs and caudal plate were deep brown. The worm is covered 

 more or less with minute spots which are dark on the back but light 

 and annulated at the sides, while there are from six to eight trans- 

 verse wrinkles on all but the thoracic and caudal segments. 



The color of the worm, when about to transform, is often of a 

 most beautiful pink or crimson. The chrysalis (F^g. 50) is formed 

 within a smooth cavity under ground. It is of a dark shiny mahogany- 

 brown color, shagreened or roughened, especially at the anterior 

 edge of the segments on the back. 



Unlike the Hog-caterpillar of the Vine, just described, this in- 

 sect is everywhere single-brooded, the chrysalis remaining in the 

 ground through the fall, winter and spring months, and producing 

 the moth towards the latter part of June. I rather incline to believe 

 however that there may be exceptions to the rule in southerly lati- 

 tudes, and that in such latitudes it may sometimes be double- 

 brooded ; for I have known the moth to issue near St. Louis during 

 the first days of August, and have this very year found two worms in 

 the same locality as late as the 25th of October, neither of which was 

 quite full grown, though the Jeaves on the vines upon which they 

 were found had almost all fallen. Apparently such premature de- 

 velopment of Sphinx moths is a well-known occurrence among the 

 different European species; for Chas. Darwin remarks that u a num- 

 ber of moths, especially Sphinx moths, when hatched in the autumn 

 out of their proper season, are completely barren; though the fact of 

 their barrenness is still involved in some obscurity.* 



The moth (Fig. 51), is of a brown-gray color variegated with 

 light brown, and with the dark spots, shown in the figure, deep brown. 

 The hind wings are pink with a dark shade across the middle, still 

 darker spots below this shade, and a broad gray border behind. I 

 once had an excellent opportunity of observing how it burst open 

 the chrysalis shell, for while examining a chrysalis, the moth emerged. 

 By a few' sudden jerks of the head, but more especially by friction 



*See Variation of Animals and Plants, etc., II, pp. 157-8, English Edition, and the references 

 there given in the foot-note. 



