226 
H E M I P T E R A . 
with numerous long and slender spines, which contribute, 
like the coronets of the frog-hoppers, to fix their shanks 
firmly when they are about to leap. The leaf-hoppers have 
been divided, by Professor Germar and other entomologists, 
into many genera, according to the structure of their legs, 
the situation of the eyelets, and the form of the head ; but 
we may retain them, without inconvenience, in the genus 
Tettigonia , proposed for them by Geoffroy, or rather adopted 
from the ancient Greeks, who gave this name to the small 
kinds of harvest-flies, calling the larger ones Tettix. 
The Tettigonians, or leaf-hoppers, have the head and tho- 
rax somewhat like those of frog-hoppers, but their bodies 
are, in general, proportionally longer, not so broad across 
the middle, and not so much flattened. The head, as seen 
from above, is broad, and either crescent-shaped, semicir- 
cular, or even extended forwards in the form of a triangle; 
its upper side is more or less flattened, and the face slopes 
downwards towards the breast at an acute angle with the 
top of the head. The thorax is wider than long, with the 
front margin curving forwards, the hind margin transverse, 
or not extended between the wing-covers, which space is 
filled by a pretty large triangular scutel or escutcheon. The 
wing-covers are generally opaque, rather long and narrow, 
and more or less inclined at the sides of the body, not flat 
however, but moulded somewhat to the form of the body, 
and the wings are rather shorter and broader, not netted 
like those of the tree-hoppers, but strengthened by a few 
longitudinal veins. The eyes, which are distant from each 
other, and placed at the sides of the head, are pretty large, 
but flatfish, and not globular as in the Cicadas ; and the 
eyelets, which are rarely wanting, vary in their situation, 
being sometimes on the top and sometimes below the front 
edo-e of the head. Notwithstanding the small size of most 
of these insects, they are deserving our attention on account 
of their beauty, delicacy, and surprising agility, as well as 
for the injury sustained by vegetation from them. 
