ments and its olive-colored slinij' covering, which last is prohably a pro- 

 tection furnished by nature ayainst the attacks of parasitic insects. It 

 is very sluggish in movement, but has an enormous appetite. Its growth 

 is rapid, full size being attained within considerably less than a month, 

 usually' about twenty-five days, the time varying a little with the nature 

 of the weather. It does not alter much in appearance during growth, 

 and ultimately reaches a length of nearly half an inch. It sheds its 

 skin four times during its larval life, and usually eats its cast skin for 

 its first meal after each moult. When full grown it moults a fifth time, 

 but on this occasion leaves its cast skin as a slender line of slime 

 attached to the leaf. The dark olive-green slimy appearance which has 

 hitherto characterized the larva is lost with this last moult (see fig. 3, 

 a, which shows last moulted skin), and in its stead it appears as a light 

 orange-yellow worm, perfectly clean and dry, with the head light col- 

 ored and only the minute circular eye-spots black (fig. .'>, h) . A green- 

 ish area shows along the posterior two-thirds of the body, which is 

 merel}' the remains of the last meal appearing through the transparent 

 skin. The larva does not feed after this _ 



moult, but crawls down the plant to the 

 ground, which it Ijurrows into actively, dis- 

 appearing beneath the surface in a very short 

 time. It penetrates to a depth of from half 

 an inch to two or three inches, usually the a' 

 lesser distance, and at the extremity of the fig. 4.-pearslug: «, cocoon; b, 

 burrow presses the soil away from itself so ^■ouu-m larva: c, pupa-aii 



enlarged ((n-iKinal). 



as to form a little cell or chamber, the sides 



of which it moistens with saliva. The drying and hardening of the 

 walls of the chamber form a sort of cocoon of firm texture and more or 

 less impervious to water (see fig. 4, a). 



During the heated season of July and August the transfoi'niation from 

 the larval to the pupal stage and from the \atie.r to the adult insect is 

 quite rapid, the pupal stage being assumed in from six to eiglit days, 

 and the adult files transforming and (Hgging out through the soil some 

 twelve or fifteen days after tlie larva, entered it. 



It seems from the studies l)y Pec^k, and in pni't conllrnied l)y my own 

 observations, that all of the larva^ of the spring brood do not transform 

 at once, but some few of them rcunain unchanged as contracted dormant 

 larva? over winter to transform the next spring. It is true also of the 

 second broods of larvie that some <tf them conu! out tlie same season, 

 while others remain over wint(;r and do not pupate until shortly before 

 the appearance of the adults in April and May. The holding over to 

 the next 3'ear of ceitain larva' of each brood is doubtless a jMovision of 

 nature to prevent the extermination of the species by any untoward acci- 

 dent, such as the absence of food, unfavorable climatic conditions, or 



