224 Wisconsin Academy of Sciences, Arts, and Letters. 
Planorbis campanulatus. 
Planorbis campanulatus rudentis. 
Planorbis bicarinatus striatus. 
Planorbis binneyi. 
Lymncea stagnalis lilliance. 
Lymnoea emarginata wisc'onsinensis. 
Enclosed Bay Succession. 
(Figure 9.) 
The rise of the w^ter overflows the lower portions of the 
shore, producing enclosed hays, which soon become filled with 
such plants as pondweed (Potamogeton), white pond-lily ( Gas- 
talia odorata) and yellow pond-lily (Nymphcea advena). The 
mollusks of such a habitat are: 
Anodonta grandis footiana. 
Anodonta marginata. 
Amnicola cincinnatiensis. 
Physa ancillaria warreniana. 
Ancylus parallelus. 
Planorbis hirsutus. 
Planorbis campanulatus. 
Planorbis campanulatus rudentis . 
Planorbis bicarinatus striatus. 
Planorbis binneyi. 
Lymacea stagnalis lilliance. 
Lymncea columella. 
Lymncea lanceata. 
It will be noted that four species (Lampsilis, Sphoerium 
Campelama and Lymnoea emarginata wisconsinensis) have dis¬ 
appeared, while five species (Amnicola, Ancylus, Planorbis hir¬ 
sutus, Lymncea columella and Lymnaea lanceata) have been 
added. This change of species well illustrates the influence of 
a changing environment. 
