EXTERNAL ANATOMY OF INSECTS. 6S? 



We next come to the Ortkoptera* ; in these the folds in 

 general are longitudinal ; and those of the Anal Area in 

 particular, either in whole or in part, exact counterparts 

 of a fan : wherever there is a straight nervure, there is 

 usually a fold or a tendency to it ; this is the case even 

 with the short oblique ones observable in the Interme- 

 diate Area of Blatta : in this tribe the Anal Area, or a 

 considerable portion of it, is folded under the rest of the 

 wing, and the whole lies on the back of the animal, so 

 that in this wing there are only two primary folds ; but 

 in those with a narrower body, as Pkasma, &c, there 

 are more, and the Anal Area, folded like a fan, lies hori- 

 zontally on the back ; the Costal is vertically applied to 

 the sides, and the Intermediate is between both, as in the 

 tegmina h . In Gryllus Latr., Gryllotalpa, &c, when the 

 wings are folded, the end of the Anal Area projects so as 

 to present the appearance of two tails c ; and in that re- 

 markable Chinese animal Gryllus monstrosus, in which 

 these tails are very long, they are convolute like those 

 of some quadrupeds' 1 . It is to be observed that in the 

 secondary folds of these wings the angles of the folds are 

 surmounted by a nervure. 



In both sections of the Hemiptera Order, as in the Co- 

 leoptera, the Anal Area is turned under the wing and lies 

 over the back of the insect; this is the only primary fold, 

 but besides there are several longitudinal semifolds or 

 secondary ones, in which one part of the surface forms an 

 obtuse angle with another; and in Tettigonia, &c, these 

 folds ramify in the wings as well as in the tegmina at the 



■ Plate XXVIII. Fig. 22. b See above, p. 608—. 



fi Stoll Grillom, t. Hi. c. /. 11 — 13. & Ibid, t.i.c.f.1,2. 



