42 THE CANADIAN ENTOMOLOGIST. 



At the time when the above deposits were made, the weather was 

 more or less cloudy, and both light and heavy rains Avere of frequent 

 occurrence. Such was its unfavorableness, that fears were entertained 

 of the complete failure of my experiments. On many occasions, eggs 

 were broken, and their contents examined with very strong magni- 

 fying glasses, to ascertain whether putridity had taken place. Within 

 a week of the time of hatching, numerous eggs were examined, and 

 the only evidence of change apparent, was a slight turbidity 

 of their contents. The v/eather for a day or two previous had been 

 exceedingly fine, and the heat rather powerful. This happy state of 

 things continued with slight, unimportant changes, until the hatching 

 process was over. Eggs, as well as chrysalids, can endure a strong degree 

 of cold without injurious etfects, provided troansformation has not already 

 commenced, when vitality receives a check from which it never recovers. 

 An alternation of wet and dry, or of extremely cold and very warm 

 weather, is exceedingly detrimental. May it not be that the extreme 

 paucity of certain kinds of insects during some years is due to the causes 

 which have just been noticed ? 



The caterpillar of this species (when hatched) is nearly three- 

 sixteenths of an inch in length, and scarcely thicker than an ordinary 

 darning-needle. Its general color is a jet black. It is armed with two 

 dorsal rows of glossy black spiniferous tubercles, those on the second 

 and third somites being the largest ; and also two lateral rows on 

 each side, making six in all. The antennae are short, black, triple- 

 jointed, and moderately tapering. The true legs are black, three- 

 jointed, and armed with short, in-curved claws ; the pro-legs occupy 

 the 6th, yth, 8th, 9th, loth and anal segments, and are furnished with a 

 double row of black cilise. 



June loth — First moulting takes place. The caterpillar now measures 

 nearly one-half of an inch. x\t first, it is greenish-yellow, but gradually 

 changes to a yellowish-brown, with a slight tinge of green when perfectly 

 dry. The caput and star-crowned protuberances still remain a beautiful 

 glossy black. Each somite, between the different rows of tubercles, is 

 diversified with a pair of black spots which ultimately become conjoined, 

 forming longitudinal lines throughout their entire length. Between the 

 segments, they are continued as obscure bands. 



With age, the color becomes a dark yellowish-brown. At this stage^ 

 the caterpillar ceases to feed, and becomes considerably shortened. It is 



