11 



with short brown hairs in addition to the longer ones, which give the 

 tubercles when magnified an appearance like velvet. The head of the 

 larva is pale brown with darker mottlings. 



The young larvae are of a blackish color covered with reddish brown 

 hairs. The head is jet black. Close examination will show projecting 

 from the back of the fourth and fifth abdominal segments a large tuft 

 of reddish brown hairs, and on the middle line of the ninth and tenth 

 segments is an orange or reddish tubercle which may be withdrawn 

 into the body. After the second spring molt the larva is about three- 

 eighths of an inch long, the yellow mark- 

 ings on the body are more apparent, and 

 the brown tufts on the back less promi- 

 nent, while the band of white dashes along 

 the sides, characteristic of the full-grown 

 larva, is noticeable. 



The pupa. — The full-grown larva spins 

 a cocoon of grayish silk, which is very 

 loose in its construction and is so far from 

 being compact that the pupa may be read- 

 ily seen thru it. The pupa itself is about 

 five-eighths of an inch long, dark brown 

 in color, with a conical spine at the end of 

 the abdomen bearing a cluster of minute 

 hooks at the tip. Smooth, j^ellowish 

 brown hairs are found scattered over the 

 abdomen and the top of the thorax. 



The cocoons are apparently spun by 

 preference among the leaves at the tips of 

 branches, and often a dozen or more larvae 

 will spin a common web within which 

 each individual forms its own cocoon and 

 transforms to pupa. The cocoons are 

 also found under fences and beneath the 

 edges of clapboards. Mr. Kirkland has 

 seen a mass of cocoons nearly 2 feet across 

 in the cornice of a house in Somerville. 



The adult or moth. — The moths (fig. 1, 

 at left) are pure white, the end of the abdomen being brownish, and 

 both sexes bear at the tip of the abdomen, more conspicuousl}" with 

 the female, a tuft of brown hairs, almost globular in form, from which 

 comes the name brown-tail moth. It is the only moth occurring in 

 America to which this description applies, and is therefore unmistak- 

 able. The female expands about 1^ inches, and the male is smaller. 



264 



Fig. 3. — Bro^vn-tail moths on electric- 

 light pole, Maiden, Mass., July 12, 

 1905. (From Kirkland.) 



