INSECTA. 449 



of it, then we cannot in any way look upon OLIVIER as its founder, 

 because DE GEER had already collected into a distinct division, to 

 which he gave the name of Dermaptera, the self-same insects which 

 are now arranged in the order of the Orthoptera. Mem. pour servir 

 a rffist. des Ins. 1773, p. 309. He characterised these insects 

 by their leathery shield-covers and the parts subservient to mas- 

 tication 1 . 



Many orthopterous insects have two or three simple eyes. The 

 antennae always consist of a great number of joints. The left upper- 

 jaw is on the whole more toothed than the right. The under-lip is 

 divided into four lobes, of which the two exterior correspond with 

 the galese of the under-jaws. 



The first thoracic segment is generally large. Ordinarily there are 

 ftnir wings; sometimes, as in the mole-cricket and many species of 

 Phasma, the anterior wings are very small, the posterior large ; in 

 Phi/Ilium, on the contrary, the hind-wings are entirely absent, and 

 there are only fore- wings or shield-covers; the instance of Perla- 

 morpha, CURTIS is entirely peculiar, where shield-covers are wanting 

 and hind- wings alone are present. The joints of the tarsus are in 

 most fleshy or spongy beneath; the number of these joints is in 

 every species the same for all the feet, and varies from three to five. 



All the Orthoptera hitherto known are terrestrial, during the 

 different states of metamorphosis. Some are carnivorous or 

 omnivorous, but the greater number feed on plants. But some 

 species often appear in great numbers and are very ravening, and 

 may cause terrible devastation ; this is especially the case with the 

 locusts, a dreaded plague of the East. 



The intestinal canal is on the whole short, and even in those 

 species in which it has the greatest relative length, it is to the 

 length of the body only as 1 or 2 : 1. The oesophagus has an 

 expansion which may be considered as a crop or fore-stomach ; this, 

 in the mole-cricket, is situated quite laterally. The muscular 

 stomach is small, orbicular, armed internally with horny teeth, 

 which are arranged in six rows. Round the inferior orifice of this 

 stomach are blind appendages of variable number; the genus Acheta, 

 for instance, has only two such, Gryllus FABR. (Acrydiwm LATR.) 

 six, Mantis and Blatta eight. Of the numerous vasa urinaria in 

 this order we have spoken above (p. 256), as also of the presence of 



1 FABBICIUS named these insects Ulonata. 



VOL. i. 29 



