No. 376. ] THE WINGS OF INSECTS. 247 
dated by Fig. 17, which represents the base of the fore wing 
of the adult, and Fig. 18, which represents the region of the 
nodal furrow of the same wing. These figures are based on a 
study of the recently emerged adult, already referred to. We 
Fic. 18. — Cicada, nodal furrow of the fore wing. 
wish to call attention especially to the coalescence of subcosta 
and radius from the base of the wing to a point near the nodal 
furrow, as this is a feature which occurs in a large proportion 
of the families of the Hemiptera. 
The changes that have taken place in the hind wing of Cicada 
are much greater than those of the fore wing, and it would be 
% 
Fic. 19.— Cicada, hind wing, young nymph. 
exceedingly difficult to understand them without the aid of 
ontogenetic study. But a careful comparison of the hind wing 
of a young nymph (Fig. 19) and the base of the hind wing of 
the recently emerged adult (Fig. 20) has cleared up the doubt- 
ful points. 
