146 INSECTA. 



In those which compose the first, all the legs are similar, and only 

 adapted for running, — they are the Cursoria, or runners. In those 

 which constitute the second, the posterior pair of thighs are much 

 larger than the others, thereby enabling them to leap. Besides this, 

 the males produce a sharp or stridulous noise — they are the Saltatoria 

 or jumpers. 



FAMILY I. 



CURSORIA. 



In this family the posterior legs, as well as the others, are solely 

 adapted for running. 



Almost all these Insects have their elytra and wings laid horizon- 

 tally on ih(; body ; the females are destitute of a corneous ovipositor. 



They form three genera : in the first or the 

 FoRFicuLA, Lin.^ 



There are three joints in the tarsi; the wings are plaited like a fan, 

 and folded transversely under very short and crustaceous elytra, with 

 a straight suture; the body is linear, with two large, squamous, mo- 

 bile pieces, which form a forceps at its posterior extremity. 



The head is exposed. 



The antennae are filiform, inserted before the eyes, and composed 

 of from twelve to thirty joints, according to the species. The galea 

 is slender, elongated, and almost cylindrical. The ligula is forked. 

 The thorax in the form of a scale. 



The researches of MM. Randohr, Posselt, Marcel de Serres, and 

 those of M. Leon Dufour in particular, have unveiled to us the in- 

 ternal organization of these Insects. The latter gentleman has dis- 

 covered two salivary glands, each consisting in a vesicle, more or less 

 ellipsoidal, situated "in the prothorax or thorax, terminated posteriorly 

 by an extremely tenuous thread, and anteriorly by a tubular, capil- 

 lary neck, which is slightly inflated near the pharynx, and then unites 

 with the corresponding portion of the other gland to form a common 

 trunk opening into the mouth. 



The digestive canal consists of an esophagus, a large elongated 

 crop, and of a short gizzard furnished internally for trituration, with 

 six longitudinal and almost callous columns, in the form of lancets, 

 separated by as many grooves, and with a valve at its ventricular 

 aperture ; of a stomach or chylific ventricle, at the posterior extre. 



into four families corresponding to the genera Forjicula, Blafta, Mantis, and Phasma. 

 The second comprises two families constituted by the genera Achela and Locusta. 

 The third section forms another family, having for its type the genera Pneumora, 

 Truxalis, and that of Gryllus, Fab., or the Acrydium, Geoff. See also for further 

 details on the Insects of this order, the Memoirs of the Academy of St. Petersburgh, 

 1812. 



This division into two great families is confirmed by their anatomy, the Insects of 

 the first having tubular tracheae only, and those of the second such as are vesicular. 



