MOTIONS OF INSECTS. 315 



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 Necj/dalis, F., in which this seems 

 a peculiarity of the male : and amongst the Hymeno- 

 jitera^ not to mention others, several species of ChaJcis, 

 F., and all that are known of that singular genus LeU' 

 cospis. 



Many insects, that jump by means of their posterior 

 legs, have not these thighs. This is said to be the 

 case with Scaphidhan, a little tribe of beetles'* : and one 

 of the same order, that seems to come between Anohium 

 and Ptilinus, 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 (Cicadiadce), the posterior tihiss appear to 

 be principally concerned in their leaping. These are 

 often very long', and furnished on their exterior mar- 

 gin 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 vio- 

 lence "*. Many of them, amongst the rest Cicada spu- 

 maria, have the extremity of the above tibiae armed 

 with a coronet of spines ; these are of great use in 

 pushing them off when the legs are unbended. This 

 insect, when about to leap, places its posterior thighs 

 in a direction perpendicular to the plane of position, 

 keeping them close to the body ; it next with great vio- 

 lence pushes them out backwards, so as to stretch the 



* Trost, Bdtmse. 40. " De Geor, iii. 161. 



