Baker — Molluscan Fauna of Tomahawk Lake , Wisconsin. 231 
Genus Strophitus Rafinesque. 
5. Strophitus ectemtulus (Say). 
Station XXII. The examples of this species are rather 
small and the shells are thinner than in individuals from 
farther south. 
Genus Anodonta (Bruguiere) Lamarck. 
6. Anodonta marginata (Say). 
Stations III, IV 1 , X, XIV s , XXII. The individuals of 
this Anodonta are usually very uniform. At Station X 
the specimens vary from the usual cylindrical shape to one 
approaching Anthony 7 s irisansj with a marked postero-dor- 
sal ridge. All inhabit rough or running water. This is 
a common species in Wisconsin, though not mentioned in 
Chadwick’s list. 
7. Anodonta implicata (Say). 
Station XXII. Apparently typical. 
8. Anodonta grandis footiana (Lea). 
Stations III, IV 1 , XIV 3 , XXII. This race is quite 
typical and shows little variation. The stations are all in 
rough or running water, which accounts, in some measure, 
for the small size and uniformity of the individuals. At 
Station III, the open lake shore, footiana forms a large 
bed, associated with Lampsilis luteola. which the muskrats 
have made good use of. A hollow tree trunk on the shore 
of this lake was found filled with the empty shells of 
Anodonta and Lampsilis, evidently representing the Alin¬ 
ing halPof a muskrat. 
Genus Symphynota Lea. 
9. Symphynota costata (Barnes). 
Station XXII. Common and typical. 
10. Symphynota compressa (Lea). 
Station XXII. One specimen of compressa was found 
in a lot of costata. It is evidently rare at this station. 
