244 THE AMERICAN NATURALIST. [VOL XXXII. 
In the wing of a nearly mature nymph (Fig. 14) the costal 
trachea extends nearly to the apex of the wing. The subcostal 
trachea is also prominent, but it is not forked. The radius is 
reduced to a three-branched condition. The media is typical. 
So, too, is the cubitus. -The first anal trachea coalesces with 
the cubital trachea for a considerable distance. The second 
and third anal trachee are also united at the base, and the 
forming veins appear as pale bands. 
The important departures from the primitive type are two: 
first, the coalescence of the first anal vein with the cubitus. 
This results in the anal furrow of the adult lying between the 
first and second anal veins; but these two are closely opposed 
Fic. 14.— Cicada, fore wing, mature nymph. 
in the fore wing of the adult, except for a short distance at the 
base of the wing, so that they appear as a single vein along 
the line of the furrow. The study of the wings of an adult 
which was killed at the moment of emergence from the nymph 
skin, and in which the tracheze of the wings are distinctly 
visible within their corresponding wing-veins, has materially 
aided us in determining the relation of the anal furrow to the 
adjacent veins. It may be said in this connection that the 
coalescence of the first anal vein with the cubitus is a common 
occurrence in several of the orders. 
A more striking departure from the primitive type is the 
reduction of the radius. For a long time we were unable to 
decide in what manner this had taken place. The usual mode 
of reduction of this vein is by the coalescence outward of the 
two branches of each half of the radial sector, leaving the 
