shorter and broader than in either of the preceding species; hyaline, 
with a broad smoky band at the tips, a spot back of the shoulder, 
and some freckles near the margin, of the same color; the marginal 
and other veins all white, alternating with numerous black rings. 
The breast, blackish; legs, dusk or brownish. 
Also found on the sweet-flag. 
Although apparently of but little importance economically, these 
species, as well as a number of others, are described, not simply to 
make the list complete, but as a means of illustrating the genus, so 
that other species, if found, may be readily located in their proper 
place. So far but few species belonging to this family have ever 
been particularly injurious, either in this country or in Europe, but 
every now and then the cultivation of a new plant, increased cultiva¬ 
tion of one hitherto but little used, or some similar cause, produces 
the sudden increase of a species previously scarcely noticed. 
Genus PSYLLA (Jumping Plant-lice.) 
In this genus the head is strongly inclined and flat above, and 
usually, if not always, obtusely triangular in front; the front cleft is 
not generally as distinct and marked as in Livia. The eyes are usually 
globular and prominent, not flattened as they commonly are in the 
previous genus; ocelli or little eyes distinct, three in number, placed 
in a triangle on the upper side of the head, one on each side, near 
the inner border of the eye, and the other in front. The antennae 
are usually as long or longer than the body, slender and thread-like; 
the first two joints short and thicker than the others; the third the 
longest, the last short with two short bristles at the tip. Beak very 
short, arising apparently from the breast, a little behind the first pair 
of legs; in repose it usually remains nearly perpendicular, composed of 
three joints, the last very short. The wings thin- and transparent, the 
front pair a little thicker than the hind pair. The hind legs adapted 
for leaping; the tarsi or feet two-jointed. 
The eggs of the species, so far as observed, are oval and somewhat 
conical in form, pointed at one end and rounded at the other, and 
furnished, usually, at least, with a kind of beak or appendage near the 
larger end. They are very commonly deposited in a cottony substance, 
and are usually yellowish or reddish. It is stated in reference to some 
species, that the female punctures the bark and places her eggs in the 
punctures, but this does uot appear to be the general rule; at least, 
the Psylla of Figure 1, deposits its eggs in the little crevices and under 
the little scales around the leaf-bud, turning the beak underneath out 
of view, and possibly slightly inserting it into the bark to secure the 
egg in its place. 
The larvae are usually somewhat long in proportion to their width, 
and often covered with a cottony substance, formed by a secretion 
which exudes from the pores of the body; but our best known and 
most common species forms an exception to this somewhat general 
rule. The pupae are easily distinguished by the two scales on each 
side, which are rudimentary wings; also by their rounder and more 
plump form. 
