OHTHOPTERA. — GRYLLID.T,. 453 



the sounds which they produce, vary in the different genera; and 

 although the males alone are ordinarily provided with them, both 

 sexes in the genus Ephippiger Latr. (in which the wings are wanting, 

 and the wing-covers are very short) ai'e provided with them, and 

 consequently able to produce a sound (^Goureau, loc. cit. sitpra.) 



Sometimes this talc-like plate exists only in one of the wing-covers. 

 In some of the species having the wing-covers of so small a size as to be 

 nearly rudimental, the posterior part of the prothorax is elevated into a 

 kind of dome over the wing-covers, and which has probably the effect 

 of increasing the sound ; this is the case with the Ephippiger vitium *, 

 a species which I found amongst the vines on the banks of the 

 Rhine. The object of the stridulation of these insects is, the calling 

 of the female ; and one of these insects has on that account afforded 

 to Brunelli an opportunity of making several curious observations 

 on the powers of hearing possessed by insects. (Le/tmcuui, De Sen- 

 sibus externis Ins. p. 23.) The song of these insects (especially 

 that of G. viridissimus Linn.) is kept up till late in the evening. 



" So chirps the grasshopper one good-night carol more ; 

 He is an evening reveller, who makes 

 His life an infancy, and sings his fill." — Childe Harold. 



The ovipositor (^ff. 55. 12. ovipositor of G. viridissimus ; Jiff. 55. 

 13. the same, with the parts separated) is composed of several flat- 

 tened plates of variable form and length, of which the insides are 

 applied against each other when at rest, but which the insect has 

 the power of opening, so as to admit the passage of an egg between 

 them. This apparatus is thrust to a considerable depth into the 

 ground, when the female deposits several eggs, and then proceeds to 

 another spot to repeat the operation. Both sexes are furnished also 

 with two short inarticulated processes at the extremity of the body ; 

 besides which, the terminal ventral segment in the males is produced 

 into a corneous plate or furcate appendage, provided with projec- 

 tions, and varying in the different species (Jiff. 55. ll. extremity of 

 abdomen of male G. viridissimus.) These insects are more commonly 

 found upon the branches of trees and plants than the Achetidos and 

 Locustidas, feeding upon the leaves. They seem, however, to prefer 

 damp situations, Decticus griseus, for instance, and Xiphidion fuscum 



* Baron Walckenaer has considered it prohablc that this insect was the Gaza in 

 the Chaldasan version of the prophets Joel and Amos. (Ann. Soc. Ent. de France, 

 1836, p. 238.) 



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