EXTERNAL ANATOMY OF INSECTS. 607 
tegmen more or less lies over the other. In Blatta, in 
which the ¢egmina are nearly horizontal, the left hand 
one covers almost half the other ?: in the other tribes of 
the Order, with little variation, the Anal Area of the 
tegmen is horizontal, and covers the back of the animal, 
and the Intermediate and Costal are vertical and cover 
its sides; the former, however, in some cases, only forms 
the angle between them. Sometimes in these the right- 
hand one is laid upon the Jeft, as in Gryllus, and some- 
times the reverse of this takes place, as in Acrida. With 
regard to the folding of the ¢egmzna, the most remarkable 
instance that occurs is that of Acheta monstrosa, in which 
the ends of both these organs and the wings, in repose, 
are folded like a fan, and then rolled up like a serpent >, 
5. Shape. The shape of tegmina is various. In the 
Blatie and some Mantes they are more or less oblong ; in 
Mantis precaria, strumaria *, and others, they incline to 
elliptical ; in Phasma Gigas and Gryllus monstrosus they 
are rather panduriform® ; in Empusa gongyloides they are 
semi-cordate®; in Pterophylla trapexiformis they are 
rhomboidal ; in Conocephalus erosus they are sinuated ; 
in Locusta they are usually dznear or linear-oblong & ; in 
Pterophylla they generally terminate in a short mucro *; 
and in some of those Mantide whose tegmina simulate 
arid leaves, in a recurved one‘. In the Homopterous 
Hemiptera the shape of these organs is less various. In 
* PrateE X. Fic. 2. ® Stoll Grillons t. i. c.f. 2. 
* Ibid. Spectres t. xxv. f. 95. and xi. f. 42. 
4 Tbid. ¢. ii. f. 5. Grillons t.i. c.f. 1. ® Ibid. Spectres t. xvi. f. 58. 
f Ibid. Sauterelles a Sabr. t. iii. f. 7. By this name (Pterophylla) I 
distinguish those Locuste F. without a conical head that are veined 
like leaves. © Stoll Zéed. ¢. vi.a.f.18. and Pirate XXVIITI.Fre. 19. 
h Stoll Sauterel ad Sabr. t.i—iii. i Ibid. Spectres t. iv. f. 14. 
