flemiplera-Fleteroptera. 9 
earlier genera they are numerous and generally longitu- 
dinal, sometimes springing from a transverse basal nerve, 
but in the Capside the neuration is very simple, consisting 
of a single well-defined nerve, which originates just beyond 
the inner angle of the cuneus, and encloses a cell on the 
membrane, its other extremity being near the outer apical 
angle of the cuneus, a nerve from this divides the cell into 
two, in some cases this divisional nerve is absent ; in the 
Cimicide there is only a basal nerve which lies close to 
the apex of the corium; in the Tingidide the membrane is 
reticulated and almost like the rest of the elytra; in the 
Corixidz the membrane is almost nerveless. 
The posterior wings are always membranous ; the neura- 
tion varies considerably but it has not been used much for 
characteristic purposes; in the Capsida the presence or 
absence of the hook-lke nerve which is emitted from the 
upper nerve of the wing cell is used for divisional purposes, 
but it is not constant, as in Asciodema some specimens 
have the nerve and some have not. 
Of the legs the constituent parts of each are first the coxa ; 
this is moderately sized in most of the genera, but very 
largely developed in the Capside ; second, the trochanter ; 
a small jot between the coxa and the femur; third, the 
femur; those of the anterior and posterior legs are often 
more or less incrassated, and in the Lygzeidz the former 
are generally armed with a spine near the centre and often 
with several smaller spines near it; fourth, the tibia; 
these as a rule do not present any great variability of form, 
but the spines which they bear insome of the Capsidee are 
useful in distinguishing genera apart; fifth, the tarsi; these 
consist of one, two, or three joints, and afford valuable 
generic characters ; in the Corixidz the posterior tarsi are 
formed for swimming, being dilated, and somewhat oar- 
shaped, fringed with long hairs; the anterior tarsi in the 
males of this family vary much in form and are useful 
characters in distinguishing the species apart; the apical 
