THE CANADIAN ENTOMOLOGIST. 229 



twelfth each have four ; the fourth and fifth each have six, and the sixth, 

 seventh, eighth, ninth, tenth and eleventh each have five small dark brown 

 tubercles on each side of the dorsal line. These tubercles are arranged 

 in two rows around each segment ; the tubercles in the anterior row 

 alternating with those of the posterior row on the same segment. Each 

 tubercle gives rise to a tuft of fine white hair. 



The larvae moulted for the first time on the 20th. They were then 

 tV inch in length and nearly cylindrical in shape. Head white, faintly 

 bilobed. Larva pale bluish-green. Tufts of hair, arising from the 

 tubercles, white and somewhat longer than prior to moulting, and some 

 of the hairs branched. In other respects the larva is unchanged. 



The larvae moulted again on the 24th. They now measure J^ inch 

 in length, and are entirely pale green in color. The tufts of white hair 

 are now quite long (as long as the diameter of the larva), and very many 

 of the hairs are branching ; some being sparsely and the largest thickly 

 branched. The tufts of hair on the three anterior and posterior segments 

 are somewhat longer than on the rest of the body. The hair of some of 

 the larvae is pearl gray in color instead of white. 



The larvae passed their third moult on the 27th. They are now $/% 

 inch long. Body entirely pale green. Head greenish white. The tufts 

 of hair are more dense and longer and a little inclined to unite in pencils. 

 Otherwise as in last moult. 



The larvae quit feeding on the 3rd of July and began to make cocoons 

 on the 4th. The full grown larvae are ^ to ^ inch in length. The 

 .lengths given ate of the larvae when at rest ; in motion they are about one 

 third longer than the measures mentioned. 



The cocoons are very slight and are made up of the hair of the larva 

 held together with a little silk. The pupa is dark brown (nearly black) 

 and is closely punctate. The anterior extremity is sub-quadrate and the 

 segmental extremity blunt. The pupa is one-half to five-eighths inch long 

 by three-sixteenths inch in diameter. 



The imagines emerged July 14th to 16th, which makes the time neces- 

 sary to complete their transformations (from egg to imago) thirty-seven to 

 thirty-nine days. The insect has here from three to four broods each 

 year, the fall brood hybernating in pupa. The larva here feeds on 

 Asclepias incarnata L., and refuses to eat Asclepias cornuti even when they 

 are just emerged from the egg and have never yet eaten any food. The 



