Baker—Molluscan Fauna of Tomahawk Lake, Wisconsin. 237 
habitats quite different from those occupied by Planorbis 
bicarinatus striatus. Unicarinatus is spiraly striated much 
as is variety striatus , though not to so marked a degree. 
The habitat of this species is the muddy bottom of a pond 
or on sticks and other debris at the mouth of the creek. 
«35. Planorbis binneyi Tryon, 
Stations II 1 , IV 1 , V, IX, XIII 1 , XIV 3 , XXIII. Binneyi , 
inhabits several diverse habitats. Stations II 1 , IX, XIII 1 , 
XIV 3 , were more or less sheltered bays where there was 
little wave action; the shells live for the most part on logs 
and floating debris, but a few prefer the sandy bottom in 
about a foot of water. Station IV 1 was an exposed bay, 
open to the full force of the waves and this Planorbis lived 
here in considerable number. Station V was an enclosed 
bay occupied by a pond-lily society; this habitat is equiva¬ 
lent to the sheltered bay as the lake Waters have free ac¬ 
cess to it. Binneyi occupied the logs in this bay. Station 
XIII was a mucky slough in a marsh, and the Planorbis 
were seen clinging to logs or crawling over the muddy bot¬ 
tom in eight to twelve inches of water. The specimens from 
this habitat are not horn colored, as is the case with those 
from the other habitats but of a reddish tinge, due probably 
to the iron in the water. The difference between this hab¬ 
itat and those of Tomahawk Lake is marked, yet there is no 
difference in the form of the shells. 
Planorbis binneyi is a common species of the northern 
tier of states and has been seen by the writer from western 
Massachusetts to Oregon. Chadwick’s reference (Wiscon¬ 
sin Moll. p. 83) to Plariorbis trivolvis Say, large form, 
probably refers to this species. 
Dali’s statement (Alaska Moll. p. 88) that binneyi “is 
not known east of the Rocky Mountains” is erroneous, a3 
it is a common Planorbis in the northeastern part of the 
United States. It is apparently a species which ranges 
from Oregon to Massachusetts, and from southern Wiscon¬ 
sin and Xew York northward. It has been identified as 
corpulentus Say, but that is quite a different species. 
