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Gyraulus circumstriatus (Tryon) 
Several specimens of a small planorbe submitted for indentification 
by Professor C. H. O’Donoghue, of the University of Manitoba, appear to 
be referable to this species, which is widely distributed in the United 
States and should be found abundantly in Canada. Specimens from 
Winnipeg river, received from Judge F. R. Latchford, are also this species, 
which lias probably been listed as parvus by previous writers. (See the 
Wis. Mon., I, p. 378, for description and figures of this species.) 
The small planorbes are very perplexing, and, as is the case with other 
species, have their maximum degree of variation within the area of the 
late Wisconsin drift sheet, where the physiography is characterized by a 
multitude of lakes, large and small. Of the Torquis group of the family, 
four species occur in Canada in the recent fauna — parvus , ardicus, circum- 
striatus, and umbilicatellus; altissimus , a Pleistocene fossil, also occurs in 
various deposits of late Wisconsin age. Ardicus and circumstriatus are 
apparently descendants of altissimus, which is the only member of the 
family known from early and middle Pleistocene time, extending from the 
earliest interval (Aftonian) to late Wisconsin time. Among both ardicus 
and circumstriatus there arc individuals which approach the ancestral form, 
as would be expected. Such arc the forms of ardicus living in Georgian 
bay and lake Simcoe, and a large form of circumstriatus from Douglas lake, 
Michigan (See Moll. Wis., I, p. 378). Gyraulus umbilicatellus has been 
listed by Mozley from Manitoba, but none lias been seen from central 
Ontario, where it should certainly be found. The little species known as 
Gyraulus (Armiger) crista (Linn.) has been recorded by Whiteaves from a 
lake west of Pine creek, northeast of Carberry, Manitoba, and it should 
be found widely distributed in Canada. Its small size (about 1-8 mm.) 
has doubtless caused it to be overlooked. 
Family, Ancylidae 
Ferrissia parallela (Say) 
Pashkokogan lake. Recorded by Whiteaves from Root river, Ontario, 
and by Mozley from several places in Manitoba. 
Ferrissia fusca (C. B. Adams) 
Bamaji lake, rare. Not before recorded from this area. 
Several Ancylidae have been listed from adjacent territory which 
should occur in western Ontario. Ferrissia rivularis (Say) and F. tarda 
(Say) have been listed from Manitoba and Assiniboia. The Canadian 
distribution of the famify is not well known owing, doubtless, to the fragile 
nature of the shells, which are rarely preserved in beach debris and must be 
collected from their natural habitat, on rocks, shells, or vegetation. 
Family, Physidae 
In the writer's “Mollusca of Wisconsin,” the American species of 
the family w T ere restricted in a group separate from the European typical 
Physa on account of the differences in the digitation of the mantle. In 
the European type of the genus, Physa fontinal is, the mantle nearly covers 
