10 MANDIBULATA. ORTHOI'TERA. 



food is various, and like the insects of the preceding order, they will 

 prey upon their own species : the indigenous species appear divisible 

 into the following families, thus concisely distinguished : — 



Corpus compressiusculum ; 



Tarsi 4-articulati ; pectus laminatum : . . .1. Gryllid^. 

 3-articulati ; 

 AntenruB iiliformes, breves ; alcB simpliciter plicatse: 2. Locus TiD^. 

 setaceae, elongata; ala: subulato-complicatse : 3. AchetiDjE. 

 applanatum, ovale ; torsi 5-articulati : . . . .4. BLATTiDiS:. 



Family I.— GRYLLID.^, Leach. 



Tarsi four-jointed ; antennce very long, slender and setaceous ; head large, 

 vertical; forehead convex, sometimes acuminated in front; eyes vertical, 

 more or less prominent ; thorax flat above, the sides rather suddenly 

 deflexed, rounded behind ; body somewhat compressed, shining, glabrous ; 

 breast mostly with two oval foliated plates ; elytra vertical, descending on 

 each side, and often longer than the abdomen, the latter compressed with 

 two processes at the apex in the male, and a lengthened compressed ovi- 

 positor in the female ; legs elongate, approximating at the base ; four 

 anterior slender ; posterior pair very much elongated, with large femora, 

 and spiuose slender tibise, which are tetragonal. 



The insects of this family are nearly all of great bulk, arising 

 principally from the length of their members, the antennae and 

 posterior legs especially, their body being comparatively short : they 

 are chiefly found in the autumnal months, and frequent hedges by 

 the sides of woods, or grassy places ; some of them are very local, 

 and appear to affect chalky regions ; others are found on trees : thei 

 males of some species make a loud stridulous noise by the friction 

 of the membranous elytra: the females have invariably a long 

 exserted ovipositor. 



The species of this family have hitherto been associated, at least 

 in this country, under one genus, viz. Acrida, but their habit is so 

 various as to call for divisions, and Mr. Curtis is even induced to 

 observe, " it is difficult to find characters that will embrace even the 

 insects that are now included in this genus :"''' I shall, therefore, 

 follow up the plan that has been lately sketched by Latreille and 

 Serville, and endeavour to divide the indigenous species into genera, 

 and which upon a prima facie appearance may be thus cursorily 

 characterized : — 



