166 THE UNIVERSITY SCIENCE BULLETIN. 
Plea striola Fieber, 1844. 
“Highly arched behind; wing covers pointed; forehead with brownish- 
red median stripe; eyes black; hind half of closing suture brown. From 
North America. 
“It is three-fourths lines long. Similar to the two preceding species, 
but noticeably narrowed and pointed behind. Grayish yellow. Over the 
front, a brownish-red median stripe. Eyes black. The entire dorsal sur- — 
face is unflecked. The wing covers behind the suture are much higher 
arched than the other species. Posterior half of suture brown, darker — 
at the margins. Legs yellowish, last tarsal segment brown at the tip. 
Femur dark brown at base. The sculpturing consists of an impressed 
point in the middle of the five or six covered reticulations clearly visible 
in the substance of the wing cover, a very short delicate seta arises from 
each puncture, which is visible only on close observation.”—Fieber in — 
Entomologische Monographien, 1844, pp. 18-19. 
Genus NOTONECTA L. 
“Head. Eyes not contiguous. Labrum attaining to about the middle 
of the second rostral segment. Last segment of antenna shorter than 
penultimate. 
“Thorax. Pronotum not very transverse. Ale present. Hemelytra 
divided into clavus, corium and membrane. Scutellum large and almost 
equal in length to the metanotum, except in N. mexicana, where it is only 
about half its length. Hind femora not attaining to the apex of hemely- 
tra. Posterior ambulacra practically contiguous. Intermediate am- 
buleara not nearly contiguous. 
“Abdomen. Median ventral carina of the abdomen is thickly pilose, 
as are the lateral margins, thus forming a waterproof covered way over _ 
the ‘gutters’ which lie, one on each side of the carina, for the conveyance 
of air. The junctures of the connexival ventral segments are always 
covered with short thick hair, and the scutellum and hemelytra are 
generally clothed with short golden yellow pubescence. The sexes are 
almost indistinguishable in size, form, colour and general appearance, 
though, of course, the female, when full of mature ova, is dilated more 
than at other times. They can be readily separated by an examination of — 
the last three or four abdominal ventral segments. These are horizontal 
in the female, rounded and anteriorly excavated in the male.” 
Specific characters suitable for diagnosis are difficult to find. Kirk- 
aldy used head measurements. These were also employed by Bueno and _ 
are used in the following tables. Color does not furnish a reliable 
diagnostic character. Kirkaldy, in casting about for some specific char- 
acters, said: 
“Great hopes were entertained by me that the male genitalia would 
furnish a reliable diagnostic character, but in the few species (N. glauca, 
N. lutea, N. irrorata and N undulata), of which suitable material was 
available, these hopes have not been realized.” 
The writer has examined the ovipositors of the females of most of the 
species in America and finds considerable specific difference in some. He 
is quite sure he could distinguish any one of the four species above men-— 
tioned from one of the gonapophyses of the female, alone. Whether Dr. 
Kirkaldy studied them with the same care and discrimination that Dr. 
Harry Knight has used with the Miride remains to be seen. 
