218 
HEMIPTERA. 
tree seems to have its musician, and the rolling of their 
drums may be heard in every direction. This circumstance, 
however, does not render it any the less remarkable that the 
lirst of the band should keep their appointed time with such 
extreme regularity. The dog-day harvest-fly measures about 
one inch and six tenths from the front to the tips of the 
wing-covers, which, when spread, expand about three inches. 
Its body is black on the upper side ; the under side of the 
head, the breast, and the sides of the belly are covered with 
a white substance resembling flour ; the top of the head and 
the thorax are ornamented with olive-green linos and char- 
acters, one of which, in the shape of the letter W, is very 
conspicuous ; the legs, and the front edge and principal veins 
of the wing-covers and of the wings are also green, and there 
is a dusky zigzag spot on the little cross-veins near the tip 
of the wing-covers ; and the valves beneath the body of the 
males are wider than long. This species has heretofore 
been mistaken for the Cicada pruinosa, or frosted harvest-fly, 
described by Mr. Say, which is found in the Middle States, 
measures two inches to the tips of the wing-covers, has a 
i white spot each side of the base of the abdomen, a second on 
the middle of the sides, and a third near to the tip, and has 
the valves of the males longer than wide.* I am not aware 
* The form and proportions of the abdominal valves have decided me to sepa- 
rate the caniculnris from Mr. Say’s pruinosn , although, with the exception of their 
difference in size, they present no other constant characters which will invariably 
