300 ReEpoRT OF THE DEPARTMENT OF ENTOMOLOGY OF THD 
from 1 to 48 hours. Those that were born free remained motion- 
less near the anal plate of the mother for from one-half hour to 
four hours. 
Distance the larve migrate-—During the active period the larvee 
miove about very freely. The distance they can migrate unaided 
naturally varies with the character of the surface over which they 
travel and with the temperature. It is not probable that they 
travel very far over loose earth, but to determine this point more 
observations are needed. During our investigations the nearest 
approach to data on this phase of the subject was in the case of 
an infested apple placed on the ground about four inches from the 
base of a small apple tree growing in the shade in the insectary. 
The soil about the tree was well packed and moderately moist. 
The apple remained for three weeks during which time the larve 
were numerous and active, but none were found on the tree. It 
igs possible that the larve did not attempt to leave the fruit, but 
a large number of cases were observed in the laboratory where 
they wandered freely from infested apples kept under similar con- 
ditions, thus indicating that they have a definite tendency to 
migrate from the fruit. 
A. more definite illustration of the power of the larve to 
migrate was furnished by a simple experiment with a single larva. 
December 27 a young larva measuring 0.2 mm. in length was 
placed on a smooth piece of paper at 10.05-a.m. The tempera- 
ture of the room averaged about 74° F. The larva traveled 
almost continuously, with occasional stops, for six hours, during 
which time it had covered 104 feet, or about 16,000 times its own 
length. 
The larve appear to have a tendency to seek sheltered places 
on the bark and fruit before settling down. This is especially 
noticeable in cases of moderate infestation. On fruit, the blossom 
end or stem end is usually sought by a majority of the larve, the 
former often being preferred. It is possible that the position of 
the fruit may have some influence, as, after the fruit turns down, ~ 
the blossom end is less often, if at all, in the direct rays of sun- 
