220 
HEMIPTER A. 
same proportion, “ a man of ordinary stature should be able 
at once to vault through the air to the distance of a quarter 
of a mile.” Some of these leaping harvest-flies have the 
face nearly vertical, and the thorax very large, tapering to 
a point behind, covering the whole of the upper side of the 
body, and overtopping even the head, which is not visible 
from above. These belong chiefly to the genus Membracis , 
to which allusion has already been made ; and, as they are 
found mostly on the limbs of trees and shrubs, they may 
receive the name of tree-hoppers.* In others the face slopes 
downwards towards the breast, the thorax is of moderate 
size, and does not extend much, if at all, beyond the base 
of the wing-covers, and does not conceal the head when 
viewed from above. Some of the insects, with this small- 
sized thorax, are familiarly called, in English works, cuckoo- 
spit, and frog-hoppers, and to others may be applied the 
name of leaf-hoppers, because they live mostly on the leaves 
of plants. 
The thorax differs very much in shape in different kinds 
of tree-hoppers (Membracidid/e), and the variations of this 
part are productive of many odd forms among these insects, 
and particularly in foreign species. Among the species in- 
habiting Massachusetts, there are some in which the thorax 
forms a thin and high arched crest over the body, as in 
Membracis camelus of Fabricius, and the van of my Cata- 
logue . 3 To these the name of Membracis, which means 
sharp-edged, is most applicable. In other species (ilf. emar- 
(jinata and sinuata of Fabricius, and concava of Say 4 ) the 
crest of the thorax is deeply notched on the top. In others 
the whole of the thorax is not elevated longitudinally in the 
middle, but only in some part ; thus M. Ampelopsidis 6 has 
an oblong square crest on the middle of the thorax ; M. bi- 
* Mr. Rennie, in the “ Library of Entertaining Knowledge," has misapplied this 
name to the Cicadas , which do not leap. 
[3 Both belong to the genus Smilia , Arnyot. — Uiilei:.] 
[ 4 j/ emarginalti, sinuata, and concava belong to Enlilia, Arnyot. — U iileh.] 
[5 M. umjidojmdis belongs to Telamona, Fitch. — Uhlek ] 
