20 DANGER OF SPREAD OF GIPSY AND BROWN-TAIL MOTHS. 
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 larve 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may be withdrawn into the body.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 markings on the body are more apparent, 
and the brown tufts on the back less prominent, 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 readily 
seen through 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, yellowish 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 larve will spin a common 
web within which each individual 
forms its own cocoon and trans- 
forms to pupa. The cocoons are 
also found under fences and be- 
neath the edges of clapboards. Mr. 
Kirkland has seen a mass of co- 
coons nearly 2 feet across in the 
cornice of a house in Somerville. 
The adult, or moth.—The moths 
(fig. 6, at left) are pure white, the 
end of the abdomen being brown- 
ish, and both sexes bear at the tip 
of the abdomen, more conspicuously 
with the female, a tuft of brown 
hairs, almost globular in form, from 
FANS which comes the name brown-tail 
Fie. 6.—The brown-tail moth (Zuproctis chrysorrhea): Fe- moth. It is the only moth occur- 
male moth above, male moth below, larva or caterpillar 
atright. Slightly enlarged. (From Howard.) 
wy 
Med 
3 MWgaisons = 
‘ 
ring in America to which this de- 
scription applies, and is therefore 
unmistakable. The female expands about 14 inches, and the male is smaller. 
Seasonal History. 
The moths fly in New England from the Ist to the 20th of July, the time varying 
with the condition of the season. In 1898 the height of the flying season is said by 
Fernald and Kirkland to have been July 16, in 1899 July 8, and in 1902 July 14. It 
is a night-flying insect, and only a few are ever seen on the wing in the daytime. 
Soon after sunset a few begin to fly, the number increasing as it grows dark, and from 
10 o’clock to midnight they swarm to the greatest extent. They are strong flyers, and 
are attracted to light. So great have been their numbers in the infested region 
that the sides of red brick buildings near electric lights have appeared perfectly 
white. It is at this time that the great spread of the species occurs, and the reason 
that the direction of the spread has been greatest toward the northeast has been the 
fact that the prevalent night winds at that time of the year seem to have been from the 
southwest. Aside from actual flight, the species has spread by being carried in the 
moth condition on railway trains and on vessels. Captains of vessels have reported 
453 
