HUNGERFORD: AQUATIC HEMIPTERA. 207 
lat., 4 to 4.6 mm.; long., 1.9 to 2mm.; lat. 4.5 to 4.7 mm. Scutellum— 
long. (measured from prothoracic groove), 1.3 to 1.4 mm.; lat., 2.3 to 2.7 
mm.; long., 1.4 to 1.5 mm.; lat., 2.7 to 2.9 mm. Insect—long., 8.2 to 9.3 
mm.; lat., 5 to 5.5 mm.; long., 9.3 to 9.6 mm.; lat., 5.6 to 6.1 mm.” Kan- 
sas, North Carolina and South Carolina are localities from which this 
species has been taken. 
Pelocoris biimpressus Monid. 1898. 
Mont., Bul. Soc. Sci. Bucarest, VII, p. 285. 
Montandon and Champion both mention this as a variety of the species 
Pelocoris femorata, as set forth in the key. Stal says it is from North 
America. « 
Pelocoris femorateg P. B. 
Palisot Beauvoris, Ins. Rec. Afr. Am., p. 237. 
(The following from Uhler, 1884.) 
“Color more or less greenish testaceous. but after death it changes to 
a pale yellow, or horn brown. It has a black line across the base of the 
labrum; on the prothorax a dark brown quadrangular spot is seen on 
the middle next the front margin; each side of this is a wide triangle 
composed of scattered dots, flanked by larger and still more remote 
flecks, and with short, almost black lines in a series across the posterior 
submargin; while the lateral margins are broadly pale. The scutellum 
is rough, and almost covered by dark brown marbled lines. The slightly 
convex wing covers are livid brownish, with two pale dots inwardly next 
to the base of the membrane, and the base of the flat costal margin is 
broadly pale testaceous. On the venter is a faint trace cf silky hair, the 
sides of the abdomen are marked with six squarish, black spots, and the 
legs are ivory white, or yellowish. The anterior tibiw are strongly 
curved, tinged with piceous and there is a dot of the same color on the 
apex of the pairs of posterior tarsi. It measures a little more than one- 
third of an inch.” 
Distribution: “Mississippi, New York, New Jersey, Pennsylvania, 
Maryland, Florida, Illinois, Wisconsin, Minnesota, Michigan, Tennessee, 
Louisiana and Carolina.”—Van Duzee. 
B. BIoLoGy or NAUCORIDA. 
General Notes. These flattened oval bugs are found amidst tangled 
growths of Nitella and other water plants. They seem to abound where 
there is a good shelter of water plants to which they cling. They swim 
through the water with an even, rapid gait, and catch their prey, which 
may consist of insects cast upon the water or any aquatic insects it 
can capture and overcome. 
Genus AMBRYSUS Stal. 
Habitat. Uhler says that Ambrysus signoreti dwells in the quiet 
waters adjacent to streams and in standing pools, especially such as are 
grassy. Another species is found in ponds in Dakota. No one seems to 
have noted the eggs or other biological matters concerning these insects. 
Genus PELOCORIS Stal. 
This genus, related to the European Naucoris of literature, has been 
more frequently studied. The notes on the European forms date back 
to an early time. De Geer noted their swimming ability and stated that 
they fly at night; that they eat all sorts of little aquatic animals. Dufour 
described the eggs of two species, N. cimicoides and N. maculata. The 
