49 
Valvata lewisi helicoidea Dali 
Kimmewin lake, rare. The immature shell of two whorls has the same 
fine sculpture as typical lewisi which changes to the coarse, rib-like sculpture 
of helicoidea between the second and third whorls. One specimen is mark- 
edly discoidal, the last whorl separated from the one preceding and dis- 
tinctly descending. This variety of lewisi is reported from Mackenzie 
region by Whittaker. It is not specifically noted b} r Whiteaves, but it is 
probable that the record of Valvata sincera from Kawinogans river, which 
is said to be small and partly uncoiled, may be the same as the specimen 
obtained by Dr. Calm. Also the Valvata sincera from lake St. Joseph might 
have been this form of lewisi ( See Walker, 1906, p. 26, for descriptions and 
figures of the true sincera and its relationship to lewisi). 
Valvata lewisi Currier is recorded from Manitoba by Mozley and 
others and doubtless inhabits central Ontario as it does the southern part 
of this province. Whiteaves records Valvata sincera from Sutton lake, 
Keewatin, but whether this is the true sincera or a variety of lewisi cannot 
be ascertained without an examination of the specimens. 
Family, Viviparidae 
Campeloma milesii (Lea) 
Hamilton lake, one immature specimen. This is referred to milesii 
rather than to decisum. Campeloma is not listed by Whiteaves or others 
from northern Ontario and our knowledge of the distribution of this genus 
in Canada is very imperfect. Dali (1905, p. 125) lists decisum only and this 
from doubtful sources, for the most part. Hanham records decisum as 
from Lake of the Woods, rare. This may possibly have been milesii, 
which is largely a lake species. Campeloma is evidently rare in central 
and northern Canada and special search should be carried on for it by 
exploring parties. 
Family, Amnicolidae 
Amnicola limosa porata (Say) 
Pashkokogan, Hamilton, Kapikik, Cat, Botsford, and Kimmewin 
lakes. Apparently common in all lakes. Recorded by Whiteaves as 
Amnicola limosa var. from Kawinogans river and lake St. Joseph, and from 
Knee lake as Amnicola limosa. No specimens from the rivers are at hand 
for comparison, but the form of rivers may be typical. All lake material 
is referable to porata. Recorded by Mozley and others from Manitoba. 
Amnicola (Marstonia) Iustrica decepta F. C. Baker 
Botsford lake, common. The specimens are large with widely open 
umbilicus. Females are most abundant. This lake form of Iustrica appears 
to be widely distributed in the glaciated region of central North America 
and is very uniform in characteristics. As far as has been ascertained, 
Amnicola Iustrica lias not been reported from Keewatin or adjacent regions 
It is not listed by Dali or Whiteaves. (See the Wis. Mon., I, p. 108, for tW 
original description and notes on this ecological variety.) 
12931—45 
