310 =©Rerport oF THE DEPARTMENT OF ENTOMOLOGY OF THE 
epimeral angle, being a little anterior of the third pair and nearer 
the sternal ridge. The first pair of thoracic setae are short and 
fine, and are near the base of the rostrum and just anterior of the 
second pair of setae. 
The abdomen has about eighty rings. The tubercles are small, 
appearing, unless carefully focused, as chitinous rings. The anal 
lobes are of moderate size. ‘Three pairs of ventral setae are pres- 
ent. The first pair are the longest and are slender. The second 
pair are very small and inconspicuous. The third pair of setae 
appear of the same thickness as the first pair but are not so long. 
The lateral setae are long and slender. ‘The genital setae are 
slender but shorter than the lateral pair. The caudal setae are 
long, thick at the base, gradually tapering to the tip. The acces- 
sory caudal setae are short and thick. The epigynium is small and 
semicircular. 
Specimens vary much in length. The average length of the 
females is from two to three hundred microns, and of the males 
from one hundred and sixty to one hundred and seventy-five 
microns, 
LIFE HISTORY. 
The winter is spent by the mites in the buds, preferably under 
the second and third layers of the bud scales. If the numbers are 
large they are often segregated into colonies, forming an entangled 
mass of fifty or more individuals in a depression or groove of the 
bud scale, more or less concealed by the pubescence. With the 
approach of warm weather in the spring the mites become active 
and may usually be seen in the greatest numbers toward the base 
of the growing bud scale where subsistence is obtained. Molting 
appears to take place about this time with many individuals of the 
colony, the cast skins being attached to the smooth portion at the 
top of the bud scale. As the buds burst there is a movement of 
the mites to the unfolded leaves in which the eggs are deposited. 
This migration takes place with the maturing of the bud scales 
during the latter part of April and early May, depending on the 
season, soon after which the discoloration of the leaves by pale 
and red colored spots occurs. The mites burrow through the epi- 
dermis of the underside of the leaf and feed upon the cellular tissue 
