180 WET GROUND COMMUNITIES 
The amphipods and sowbugs of the earlier stages are still present. This 
is the breeding-place of such mosquitoes as the little smoky mosquito 
(Aedes fuscus) (Fig. 132, p. 178) (145, 99¢). 
3. COMMUNITIES OF MARGINS OF BODIES OF WATER 
There is always a narrow area along the margins of bodies of water 
which is difficult to classify as water or as land. The association of 
this area is the one with which we now have to deal. 
Along the margins of young ponds and lakes is an area which is 
characterized by being made up of wet sand or mud which is sub- 
merged at high water and moist at 
other times. 
a) Association of the terrigenous mar- 
gins of large lakes (Fig. 133) (Stations 
57, 58; Table XXXVIII).—Here we 
find the springtails the simplest in- 
sects, the shore bugs (150), Saldidae, 
especially Salda humilis Say, a large 
number of tiger-beetles (151) (Cicin- 
dela hirticollis) (Fig. 134) (C. cupras- 
cens), together with numerous small 
flies. 
The ground beetle (Bembidium 
carinula) (Fig. 135) and numerous 
scavengers are common because the 
beach is often strewn with dead ani- 
' mals which have floated ashore. The 
ne Ba0,, Phe bare pond and mye relations of the drift to other com- 
margin toadbug (Gelastocoris oculatus) ; aE : z - 
greatly enlarged (after Lugger). munities will be discussed in the 
chapter on dry forests. The spotted 
sandpiper feeds here, and with the piping plover often breeds not far 
from the water’s edge. Under conditions of rapid recession of the lake 
such a margin is separated from the wave-action. It is then rapidly 
transformed into the next association. 
b) Association of the terrigenous margins of ponds and small lakes 
(Stations 30, 40; Table XX XIX).—This association differs from that of 
the large lake in that the scavengers are absent and the animals much 
less active, not moving about so rapidly. Here we find springtails, 
Saldidae of another species, and the toadbug (Gelastocoris oculatus) (150) 
(Fig. 136), which is colored like the ground and is found hopping about 
