148 
College of Forestry 
TABLE NO. 9. 
Fila- G 
mentous | Desmids. | Diatoms. iy 
algee. mee 
Galbaiemarguvata canadensis. anne | 2 eee eee x 
Galbamnalusinisme reer x x p, amet [PSRs 
Pseudosuccinea columella...:.| ........ x x x 
Atcellaynaldemanivcer:) orev) sovrtrcies elt ee eee eee x 
FLONGTDISIOLCOTINGLUS epee | ei ee eooe eo: Le eee x 
Planorbis trivolvis.......... x x Xo Rll aaeemecne 
Planorbis campanulatus..... x ax p RD (ae BP ok ES 5 
FARYSG Meter OSTTO PNG see eee| ee x Xx x 
UDG CHLCULOTUT. oe 6s.0 39 SallMa8os 6 Gac x x x 
Gontobasis livescens.......2| -.55+-.- x Koti oe ae 
Gleason (1908, pp. 63-64) records the following species 
as living on the under side of pond-lily leaves, one-third of 
all leaves having one or two shells on them. 
' Valvata tricarinata. 
Galba catascopium. 
Valvata sincera nylanderi. 
Amnicola limosa. 
Physa species. 
In an inland lake (op. eit.), the bottom of which was cov- 
ered with a thick mass of twigs and coarse vegetation, sev- 
eral species lived and probably fed on the dust-fine detritus, 
as well as the decaying vegetation. ‘These are: 
Valvata tricarinata. 
Planorbis exacuous. 
Planorbis antrosus. Valvata sincera nylanderi. 
Amnicola limosa. Pisidium species. 
H. B. Baker (1911, p. 164, et. seq.) lists the following 
relation between mollusks and vegetation: 
Planorbis exacuous, on lily pads 
under side. 
Planorbis hirsutus, on lily pads, 
under side. 
Planorbis deflectus, on lily pads, 
under side. 
Planorbis bicarinatus, in alge, 
principally Vawceheria. 
Planorbis trivolvis, on lily pads 
and among algze. 
Planorbis campanulatus, 
pads and Potamogeton. 
on lily 
