
AQUATIC INSECTS OF FRESHWATER 

streams and marshes. The toad-like appearance, the short and broad 
body, mottled color and protruding eyes led to the popular designation. 
They are '4 to 3¢ inch long, are all predaceous and live principally on 
spawn, insect larva and small snails. The most generally distributed 
species of the United States are Galgulus oculatus, Pelogonus americanus, 
Fig. 204, and Mononyx stygicus. 
SHore-Bucs belong to the family of Saldidz, 
of which twelve species inhabit the United States, 
four on the Atlantic Coast. They may often 
be seen in considerable numbers on the margins 
of water ways and take flight when disturbed but 
soon alight. Their color is dark grey with white 
7; to 36 inch 
and yellow markings, and their size : 
in length. The most generally distributed 
Eastern United States species are Sa/da signoretit, 
Fig. 205, 8. pellita, 8. splacelata and 8. anthracina. 
BroApD-SHOULDERED WaATER-STRIDERS be- 

FIG, 205. Shore-bug, Sa/da 
signoretti, Enlarged. 
long to the family of Veliudz and are distinct 
and different from the true Water-striders. They are smaller, much 
broader across the thorax and thicker of limb, all of them aquatic in habit 
and almost constantly on 
the water, congregating 
in school of hundreds. 
The most @enerally. 
distributed species of the 
Atlantic Coast States are 
Hebrus americanus, Fig. 

BIG eae! Broad-shouldered 206, and Khagovelia col- 
Nae ee lars Wig: Bog sbot ye 
small size. All are pre- 
daceous and feed on the juices of insects which fall into the water, mos- 
quito larve and the tiny alevins of fishes, when they come to the surface 
of the water to take air. 
WarTER-STRIDERS belong to the family of Hydrometride, slender 
long-legged insects which dart about on the surface of ponds and pools 
of both fresh and salt water. Some species are winged and others wingless, 
varying in length from % to 5% inch. The elongated body has very 
closely folded wings and long hairlike legs, both covered with minute 
hairs, which prevent the insect from becoming wet and sustain it upon 
the surface of the water, the legs being almost continuously lifted to 
prevent their becoming wet, in which case the insect would sink into the 
FIG. 207. Broad-shouldered Water- 
strider, Rhagovelia collaris. Enlarged. 
256 
