LEAF-BUGS. 63 
black, but possesses no white spots on the wings. During July 
some fields of sugar beets were swarming with them, but they 
disappeared soon afterwards without causing any apparent in- 
jury. 
Another smaller and dark bug, belonging with the one just 
mentioned to the sub-family Plagiognatharia, was also found in 
the same fields, but caused no injury. It is called Plagiognathus 
obscurus Uhler. 
Hyaliodes vitripennis Say. (The Glassy-winged Bug). 
This is really a beautiful insect, sometimes found in large 
numbers in early autumn upon the wild and cultivated grape- 
vines, and the black and red oaks, where it feeds on tender in- 
sects. It can be recognized by the neck-like proportions of the 
prothorax. See Fig. 52. The eyes project prominently from 
the sides like beads, and the front is bluntly rounded. The base 
Fic. 52..—Hyaliodes vitripennis Say. After Riley. 
of the prothorax is broadly convex, the wing-covers are flat and 
broadly elliptical, with the costal edge strongly carinate. The 
insect is yellowish-white, with the basal joint of the feelers, 
back part of the prothorax, and a band across the apical end of 
the almost transparent wing-covers red, sometimes black; the 
prothorax is coarsely punctured, and the forward lobe, the last 
two joints of the feelers, the tip or more of the second joint, 
and the base of the scutellum, are black. It is a small but active 
being, measuring about two-thirds of an inch in length. 
Wherever the leaves of the wild grape are covered with 
the peculiar leaf-galls of the Phylloxera, an insect described 
later, we can be certain to find the bug in large numbers, actively 
engaged in sucking the lice. For this purpose the young bugs 
