55 
There should be many more species of the Lvmnaeidae found in 
northern and central Ontario than have been recorded. The following 
species and varieties are known from adjacent territory and several have 
been recorded from the vicinity of Hudson bay: 
Lymnaea slagnalis sanctaeviariae Walker — Manitoba (Mozley) 
Stagnicola emargimita canadensis (Sowb.) — Minaki, Winnipeg river, Oat. (Mozley) 
S 'tagnicola emarginata angulata (Sowb.) — Manitoba (Mozley) 
Stagnicola lanceata (Gould) — Manitoba (Mozley) 
Stagnicola palustris clod vs (Sav) — Manitoba (as palustris , Mozley) 
Stagnicola preblei (Dali) — Knee lake, Keewatin (Dali) 
Stagnicola vahlii (Beck’ M oiler) — Hannah bay, near Moose Factory 
Hudson bay (Dali); Manitoba (Mozley) 
Stagnicola arctica (Lea) — Moose river, Hudson bay (Drexler) 
Harricanaw river, Hannah bay (Whiteaves) 
Stagnicola umbrosa (Say) — Rainy lake and Seine river, Out. (Say) 
Stagnicola caperata (Say)— Moose Factory (Dali); Manitoba (Mozley). This species 
should be found rather abundantly in northern Ontario 
Stagnicola walkeriana F. C. Baker— English river, near junction with Winnipeg river; 
Ijost lake, near Minaki, Ontario (Mozley). This is recorded as apicina Lea, but 
it is not that species. Lake of the Woods (TvennicottL ( Sec Baker, Wis. Moll., 
I, p. 247.) 
Fossaria modicella (Say) — Manitoba (Mozley) 
Fossaria parva (Lea), var. — Manitoba (Mozley) 
Fossaria parva sterkii (F. C. Baker) — Manitoba (Mozley) 
Fossaria dalli (F. C. Baker) — Manitoba (Mozley) 
Fossaria umbilicata (C. it. Adams) — Manitoba (Mozley) 
Pscudosuccinea columella (Say) — Manitoba (Dali) 
Pseudosuccinca columella casta (Lea) — Manitoba (Mozley) 
Family, Planorbidae 
Helisoma antrosa royalensis (Walker). Plate II, second row. 
Bamaji, Bt. Joseph, Hamilton, Cat, and Botsford lakes; outlet of 
Bamaji lake on rocks in rapid water. Most abundant in lake Bamaji. 
All of the anfrosa-Iike shells of the collection are referable to this race, 
first described from Siskowit lake, isle Royale, lake Superior, and previously 
known only from the type locality. The peculiar sculpture mentioned by 
Walker, the more or less regular rib-like vertical sculpture, is markedly 
developed on the Keewatin specimens, and is even more regular than on 
some of the Isle Royale specimens, closely resembling that of Helisoma 
corpulenla , as mentioned by Walker. There is considerable variation in 
the form of the aperture, in some individuals the form being decidedly 
triangular, the upper part of the aperture raised above the dorsal margin of 
the body whorl, in others this area is almost in a line with the body whorl. 
It is probable that some of the records of Planorbis bicarinatus pub- 
lished by Whiteaves are referable to this variety. That from lake St. 
Joseph is certainly the same and the Kawinogans River record may be the 
same. The Albany River material is uncertain, but the Knee Lake speci- 
mens are probably referable to royalensis . Dali’s Moose Factory record is 
probably one of the lake varieties and not the typical antrosus of rivers. 
The species once called Planorbis bicarinatus Say, and now known as 
Helisoma antrosa (Conrad), though fairly uniform in the rivers and creeks 
of the central and southern part of the United States, becomes, in the 
lakes of the north, beyond the terminal moraines of the late Wisconsin 
