The Relation of Mollusks to Fish in Oneida Lake 93 
Planorbis trivolvis, var., common. Physa ancillaria warreniana, com- 
Planorbis hirsutus, rare. mon. 
Ancylus parallelus, abundant. Bythinia tentaculata, not common. 
Amnicola lustrica, not common. 
HIRUDINEA. 
Leech (Hamopis marmoratis) . 
CRUSTACEA, 
Crawfish (Cambarus propinquus) . 
INSECTA, 
Water-penny, beetle larve (Psephe-  Caddis-fly larve  (Helicopsyche 
nus lecontet). borealis) . 
A type of habitat, which should probably be classified with 
the water-edge type, occurs in Station XXX, on Frenchman 
Island (Fig. 22). This is partly protected by a beach ridge, 
behind which the lagoon-like habitat has been formed. ‘There 
are one or more small, open channels which connect the lake 
with the lagoon. The beach ridge is covered with Buttonbush 
and Swamp Loosestrife, which further protects the quiet pvol 
behind the bar. Quiet water vegetation fills the lagoon, con- 
sisting of : 
Broad-leaved Arrow-head (Sagit- Larger Blue Flag (Iris versi- 
taria latifolia) . color). 
Smith’s Bulrush (Scirpus smithtvi). Water Willow (Dianthera ameri- 
Sedge (Carex trichocarpa). cana). 
The last is a remnant of the lake shore vegetation, whicl: 
persists because of the open channels. It will finally dis- 
appear when the lagoon is completely shut off from the lake. 
(See page 72.) 
The animal life noted below occurs more or less abundantly 
in this lagoon. Minnows and young fish were more or less 
abundant in this habitat, evidently feeding. 
MOLLUSCA, 
Elliptio complanatus, rare, emi-  Planorbis trivolvis, var., abundant. 
grant from Type I. Planorbis campanulatus, not com- 
Lymnea stagnalis lillianw, com- mon. 
mon. Physa ancillaria warreniana, not 
Galba catascopium, common, emi- common. 
grant from Type I. Succinea retusa, not common. 
