THE OTTAWA NATURALIST. 
VoL. XIX. OTTAWA, JUNE, 1905. No. 3 
—NOTES ON SOME FRESH-WATER SHELLS FROM THE 
YUKON TERRITORY. 
By J. F. WHITEAVES.* 
Among the zoological collections in the Museum of the Geo- 
logical Survey of Canada, there are a few fresh-water shells from 
the Yukon Territory, which have not yet been reported upon, 
though they are by no means devoid of interest to the student of 
the geographical distribution of the mollusca. 
Most of these shells were coliected by the late Dr. G. M. 
Dawson, in 1887, at four localities, viz., from Frances Lake, at the 
head of the Liard River; from Finlayson Lake, between Frances 
Lake and the Pelly River; at the Lewes River; and from Lake 
Marsh or ‘‘Mud Lake,” one of the tributaries of the Lewes River. 
The remainder were collected by Mr. Joseph Keele in 190j, from 
the Stewart River, near Mayo River. 
The Cycladidz in these collections have been kindly deter- 
_ mined by Dr. V. Sterki, and most of the Gasteropoda by Dr. W. 
H. Dall. The species represented in them are apparently as 
follows. 
PELECYPODA. 
Spherium Walkeri Sterki. 
Frances Lake, one valve; and Finlayson Lake, two perfect 
specimens. In 1904 Mr. W. McInnes collected a few living shells, 
which were referred to this species by Dr. Sterki, from the Atta- 
wapiskat River, Keewatin. The types of S. Walkeri are from 
sake Michigan. 
* This paper and the following one are reprinted from ‘ The Nautilus’ for May, 1905. 
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