616 EXTERNAL ANATOMY OF INSECTS. 
few diverging longitudinal nervures which occasionally 
by a ramification here and there form an areolet*, but 
there are seldom any traversing nervures. ‘The Apical 
Area is usually most distinguished by nervures, in some 
forming several areolets, as in Aradus, in others running 
parallel to each other, nearly to the end of this area, as 
in Belostoma, grandis, where they are met by a travers- 
ing nervure; the object of this is doubtless to strengthen 
the membrane. 
7. Both tegmina and hemelytra are most commonly 
naked, yet very short hairs are found. on those of some 
species of Cercopis, and in many more instances in those 
of the latter description, as in Notonecta, several Lygai 
and Reduvii, &c. 
8. Colours in hemelytra are very various, and in many 
instances are peculiar to families; in certain Lygai (L. 
Hyoscyami, &c.) black and red ;in Rhinuchus compressipes 
and affinities a dingy black ; in some Reduviz black with 
a large white spot;—but it is needless to enlarge further 
on this subject. 
9. That hemelytra are used in flight is evident not only 
from the large space allowed for their muscles», but like- 
wise from a circumstance noticed by M. Chabrier, that 
in flight, in the Pentatome Latr., the corium of the he- 
melytrum is fixed to the wing; in which case both must 
describe the same arc. 
iv. Wings. We are next to consider organs which are 
exclusively appropriated to flight, and therefore are pro- 
perly denominated winys. These in the Orders that 
have elytra, tegmina, or hemelytra, are the pair that cor- 
* Pirate XXVIII. Fic. 23. © Chabrier Analyse, &c. 23. 
