MOTIONS OF INSECTS. 315 
laughed at for it, and have ascertained that, compara- 
tively, it equalled that of the locust, being also two 
hundred times its length. Being affected by muscular 
force, without the aid of wings, this is an astonishing 
leap.—There are several insects, however, that, although 
they are furnished with incrassated posterior thighs, do 
not jump. Of this description are some beetles be- 
longing to the genus Necydalis, (Oedemera, Oliv.) F., 
in which this seems a peculiarity of the male: and 
amongst the Hymenoptera, not to mention others, se- 
veral species of Chaicis, F., and all that are known of 
that singular genus Leucopsis. 
Many insects, that jump by means of their posterior 
legs, have not these thighs. This is said to be the 
case with Scaphidium, a little tribe of beetles*: and one 
of the same order, that seems to come between Anobium 
and P#ilinus, found by our friend the Rev. R. Sheppard, 
and which I have named after him Choragus Sheppardi, 
is similarly circumstanced.—In the various tribes of 
frog-hoppers (Cicadiada), the posterior tibize appear to 
be principally concerned in their leaping. These are 
often very long, and furnished, on their exterior margin, 
with a fringe of stiff hairs, or a series of strong spines, 
by pressing which against the plane of position they are 
supposed to be aided in effecting this motion. On this 
occasion they bend their legs like the grass-hoppers, and 
then unbending kick them out with violence’, Many 
of them, amongst the rest Cicada spwmaria, have the 
extremity of the above tibise armed with a coronet of 
spines; these are of great use in pushing them off when 
2 Trost, Beitrage, 40. > De Geer, iit. 161. 
