333 The Lawreyician Formation, 



1. Canada, and tlie greater portion of the continent north of 

 40° of north latitude, is covered over with a deposit consisting of 

 clay, sand, gravel and broken stones, the ruins of all geological 

 formations mixed confusedly together. 



2. The lower part of this deposit is unstralified, and constitutes 

 what is called the " drift," while the upper portion is distinctly 

 stratified, consists of materials which appear to have been accumu- 

 lated during a period of less violence, and contains organic remains. 

 This part of the deposit is called the Lawrencian. West cf 

 Kingston, the formation is not known to contain marine remains, 

 although, in other respects, it is similar to that lying in the country 

 east to the mouth of the St. Lawrence. 



3. The rock beneath the drift is smoothed, polished and grooved 

 with long parallel scratches. 



4. There is some evidence to induce the belief that the boulders 

 have travelled in the direction of the grooves in the rocks. 



5. There is some evidence to shew that from the Island of 

 Montreal the drift moved north-westerly up the St. Lawrence, 



6. We have also some proof that it moved in the upper 

 part of the Ottawa in a general direction from north-west to the 

 south-east, down the valley of the Ottawa, and in a direction at 

 right angles to the drift of the St. Lawrence. 



7. Althouo-h in certain districts the course of the drift has been 

 either towards the ea?t or west of south, yet upon the whole, it has 

 m^oved southerly, except in the neighbourhood of high mountains^ 

 where local centres of dispersion have been ascertained. 



The above summary contains the principal facts, but there are 

 many other phenomena connected with the events of the period 

 of the drift, such as the river and lake ridges and terraces, the 

 conveying of rocks from lower to higher levels, and others of an 

 analagous nature, of which we may hereafter give some account. 



The following are some of the fossils most frequently found in 

 the Lawrencian deposit of Canada : 



Fig. 1. Saxicava ragosa. — This little shell varies much in its 

 form, and belongs to a group of species not easily distinguished from 

 each other on account of these variations. This species is, however, 

 the only one of the genus found fossil in Canada, and may be easily 

 recoo"nised by its elorgated shape and rough concentrically stri- 

 ated exterior. It is a member of the family of Lithophagid.b, 

 or " stone-eaters," so called, on account of the wonderful faculty 

 they possess of boring holes in rocks, where they permanently 



