ORTHOPTERA. 155 



Those species in which the males produce their stridulation only 

 by rubbinpr their thighs ap^ainst the elytra or wing's, and whose fe- 

 males are destitute of a salient ovipositor, are distinguished from the 

 precedin.2;' ones by their antennne, which are sometimes filiform and 

 cylindrical, and sometimes ensiform or clavate, and always at least 

 as long as the head and thorax ; their elytra and wings are always 

 tectiform or inclined, and their tarsi are triarticulated. They have 

 five or six caeca, and their biliary vessels, as in most of the order, are 

 directly inserted into the intestine. 



The ligula of the greater number is merely bipartite. They all 

 have three distinct simple eyes, the labrum emarginated, the mandi- 

 bles multidentated, and the abdomen conic il and compressed laterally. 

 They leap better than the preceding ones, fly higher and longer, and 

 feed voraciously on vegetakes. They may be comprised in one single 

 genus, ihat of 



AcRYDiuM, Geoff., 



Which maybe subdivided as follows: 



Some have the mouth exposed, the ligula bifid, and a membranous 

 pellet between the terminal hooks of the tarsi. Such are 



Pneumora, T/iunb. — parlim Gryllus bulla, Lin., 



Distinguished from the following by the posterior legs, which are 

 shorter than the body, and less adapted for leaping, and by their vesi- 

 cular abdomen, at least in one of the sexes. 



I'heir antennae are filiform. 



They are only found in the most southern part of Africa *. 



Proscopia, Kliig. 



Apterous Insects, with a long and cylindrical body; their head 

 destitute of ocelli, is prolonged anteriorly in the manner of a cone 

 or point, bearing two filiform antenn?e, shorter than itself, and com- 

 posed of seven joints at most, the last pointed. Their posterior legs 

 are large, long, and approximated to the intermediaries, which are 

 more than usually remote from the anterior ones. These Orthoptera, 

 peculiar to South America, form the subject of an excellent Mono- 

 graph, published by M. Kliig. 



Truxalis, Fah. — Grvllus acrida, Lin. 



The Truxales, by their compressed, prismatic, ensiform antennae, 

 and by their pyramidally raised head, are removed from all other 

 Orthoptera f- 



Lus. Finally, the Scaphur.e of M. Kirby — Lin. Trans., Encyc. Method. — or my 

 Pennicornes, resemble ordinary Grylli, but their antennae are bearded inferiorly, and 

 their oviduct is scaphoid. 



For other genera, see Toussaint Charpentier, and the Mem. of the Imper. Acad, 

 of St. Petersburg, where Thunberg has established new generic sections. 



* Pneumira sexcjuttata, Thunb., Act. Suec, 1775, vii, 3 ; — Gryllus inanis, Fab. ;^ 

 P. immaculata, Thunb., lb., vii, 1 ; — G. papillosus, Fab. ; — P.maculata, Thunb., lb., 

 vii, 2 ; — G. variulosus, Fab. 



t Gryllus nasutus, L. ; Roes., Insect., II, Gryll. iv, I, 2. The antennae are false ; 



M 2 



