Canada 
Victoria Memorial Museum 
Bulletin No. 45 
BIOLOGICAL SERIES No. 12 
LIST OF QUATERNARY AND TERTIARY DIATOMACEM 
FROM DEPOSITS OF SOUTHERN CANADA 
INTRODUCTION 
V. L. Eardley-Wilmot, Mines Branch, Department of Mines, Ottawa, 
sent me sixty-seven samples of Canadian diatomaceous earths which he 
had collected in 1923 and 1924. An examination indicates that they may 
be divided, geologically, into two distinct groups. The eastern samples 
represent deposits in Nova Scotia, New Brunswick, Quebec, and Ontario 
and contain post-Glacial species only: these occur in the peat and mud 
formations of numerous lakes. The western samples are from British 
Columbia and are from both post-Glacial and Tertiary sediments, the 
latter occurring in the vicinity of Quesnel. 
The eastern deposits vary considerably in the aggregate of species 
included, but certain species appear to be almost invariably present. 
Among these widely distributed forms may be mentioned Eunotia major, 
Cymbella ventricosa, Stauroneis phoenicenteron and Pinnularia major. 
Eunotia and Pinnularia predominate in the number of specimens and 
in the variations of the species. Of all the genera Eunotia varies 
more than any other and it may be said to characterize the deposits. 
The samples most prolific in diatoms are those from Earltown and Folly 
lakes in Nova Scotia, and Fitzgerald lake in New Brunswick. The most 
remarkable deposit is that of Jacquot river, Quebec, which resembles no 
other deposit in North America. 
Many of the samples are from peat deposits, and, therefore, the 
following observations on preparing for study diatoms from such deposits 
may be useful. 
Some of the samples studied required no cleaning whatever. The 
material from Colbert township, Quebec, was so pure and in such a friable 
condition that it was necessary only to place a minute quantity, about as 
much as would be held on the end of the blade of a penknife, in a homoeo- 
pathic vial and add sufficient water. By diluting with pure water until the 
liquid showed a pearly appearance when held up to the light the diatoms 
were ready for mounting. In most cases, however, the material was boiled 
in a solution of carbonate of soda and if the lumps were broken down the 
liquid was decanted into a glass beaker with pure water, allowed to settle a 
few hours, then decanted again, repeating the addition of water until the soda 
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