HUNGERFORD: AQUATIC HEMIPTERA. 33 
time, unable to settle the point. O. banksi can readily be separated from 
americanus by its difference in color, markings, and the character of the 
pronotum. Apex of membrane is more narrow than in americanus.” 
O. americanus Uhl. 1876. 
Bul. U. S. Geol. Geog. Surv. 1, p. 335. 
“Broadly oval, slaty-blackish, opaque, the pronotum a little narrower 
than the abdomen. Head polished, minutely punctured in part; invested 
with very sparse prostrate pubescence, which is more dense beneath; 
rostrum reaching the end of the second ventral segment, blackish-piceous 
on the swelled base, the remainder pale rufo-testaceous; antenne pale 
piceous; face obsoletely carinate, each side with a series of oblique 
wrinkles, its anterior and lateral boundaries carinated. Pronotum trans- 
verse, velvety blackish, with a few short wavy lines and some dots of 
bluish lead-color, and remotely golden pubescent; the lateral margins 
slightly oblique, only a little narrowing anteriorly, and rounding against 
the anterior angles, which are distinct and almost acute; touching the 
margin a little way back, each side, is a small triangular yellow spot; 
posterior angles subrectangular; the. posterior margin waved each side 
of the center, where it is also a little yellowish. Pectoral surface dull 
black, with very sparse sericeous scales exteriorly; the spots of the dorsal 
margin equally visible beneath; sternal margins piceous. Legs dull pale 
piceous-yellow. Hemelytra broad, widening posteriorly, velvety black, 
pubescent, sprinkled with golden pubescénce, spotted and dotted with 
bluish lead-color; the costal margin yellow, and with five small yellow 
spots; membrane bluish lead-color, with the nervures black. Venter 
piceous black, densely, minutely sericeous pubescent, the edges of the 
segments and the tip of the last one a little reddish-piceous. The con- 
nexivum is unspotted, and the surface of the tergum black, polished,’ with 
rufo-piceous edges to the segments. 
“Length, 5 millimeters. Width of pronotum, 214 millimeters. Width 
across the hemelytra, scantily 3 millimeters.” 
Has been found in Nebraska, Illinois, Texas, Arizona, Massachusetts, 
New York, New Jersey, Pennsylvania, Maryland, North Carolina and 
' Florida. 
B. BIOLOGY OF THE OCHTERIDA. 
General Notes. These bugs are spritely fellows, dark in color, that 
live upon the shores. They are predatory in habit. 
Habitat. Uhler says of O. americanus: “This is a gay, active little 
insect, which measures enly one-fourth of an inch in length, and lives 
among the grass and weeds on the margins of brooks and ponds from 
Massachusetts to Texas. 
Hibernation. Dufour said that these insects appear in April. Thus 
they overwinter as adults. Practically nothing is known of their life 
history. Dufour describes the nymph of a species. But concerning the 
egg, number and length of the instars, ete., we have no data. 
Feeding Habits. Uhler says that the fore legs of O. americanus “are 
slender and fitted for running, not calculated for seizing and holding prey, 
as in Galgulus and Mononyx. The rostrum is, however, a dreadful instru- 
ment, sharp as the finest needle, extremely thick and stout at the base, 
and a deadly probe to a poor larva of horse-fly or other insect which lives 
next to the surface of the ground in situations near water.” 
