DISTANCE FIKST-STAGE LARVAE CAN CKAWL. 
29 
seek places which are protected from the sun, and in such situations 
pupation takes place. The egg masses are deposited near the cases 
from which the females emerged. Hence it is seldom possible to 
find egg clusters on the upper sides of the branches or twigs of trees, 
because the lower sides furnish more protection and they are sought 
by the caterpillars before pupating. For this same reason it is 
usually possible to find many egg clusters on tree trunks just above 
the ground (PL XI, fig. 1), especially if there is grass or other mate- 
rial which would furnish protection. Many larva?, however, crawl 
from the trees and seek secluded places, sometimes at a considerable 
distance from their food plants, and rubbish piles, stone walls (PL 
XI, fig. 2), lumber piles (PL III), outbuildings, or other protected 
places are often found 
Mm . 
Pig. 2. — Female pupal case and egg clusters of gipsy 
moth on stone foundation under woodwork of house 
Arrows A indicate location of egg clusters ; arrow B 
indicates location of pupal case. (Original.) 
badly infested with 
egg clusters. 
The larvae which 
hatch in such situa- 
tions must of necessity 
find suitable food if 
they are to survive, 
and the more traveling 
it is necessary for them 
to do to accomplish this 
purpose the "greater 
chance there is that 
dispersion by the wind 
will take place. For 
instance, egg clusters 
are frequently depos- 
ited beneath porches or on the underpinning of houses (fig. 2), where 
it is impossible to destroy them without first removing a part of the 
building. After hatching takes place the larva? can commonly be 
found wandering about in search of food. They often crawl to the 
roofs of the buildings, and if they spin down from such a location, 
which often happens, there is ample opportunity for dispersion b} r 
the wind. 
As a rule the location of the egg clusters and the distance that the 
larvae have to travel for food are important factors, because hunger 
causes them to search for food, and activity is essential to dispersion. 
DISTANCE FIRST-STAGE LARVAE CAN CRAWL. 
It is important to know how far first-stage larvae can crawl, as 
upon this factor depends the chance for the establishment of many 
new colonies. Experiments reported by Forbush and Fernald show 
that newly hatched larvae have crawled from 36 to 144 feet before 
