[amr] GEOLOGY OF SOME CITIES IN EASTERN CANADA 151 
Distacodus incurvatus, Hinde; Prionodus? politus, Hinde; Prionodus 
furcatus, Hinde. 
In his “ Paleontology of Ontario,” Prof. H. Alleyne Nicholson has 
described and recorded hitherto the most complete list of fossil organic 
remains from the Lorraine of Toronto and its neighbourhood comprising 
thirty-two species. 
Post-Tertiary System.—These are by far the most interesting and 
better developed formations in and about Toronto. They constitute a 
thickness of from a few to several hundred feet of stratified and un- 
stratified materials derived for the most part from the subjacent forma- 
tions, and those to the north and east along the line of trend of the 
great Labradorean glacier. A large amount of detailed stratigraphy 
and paleontology has already been accomplished in this very fertile field 
of geological investigation. Through the writings of Prof. A. P. Cole- 
man, Professor Chamberlin, Dr. George J. Hinde, Dr. 8. H. Scudder, 
and others, the history of the succession of glacial, inter-glacial and sub- 
sequent formations up to the more recent deposits of silts, sands and 
gravels, of Lake Ontario, and their fauna have been made known. 
The Labrador formation and its associate, the Toronto formation.— 
Immediately overlying the glaciated surface of the subjacent Lor- 
raine formation, may be seen in many cuttings and outcrops, a 
bluish-gray till or boulder clay which was evidently deposited by land 
ice, resting upon the palæozoic sediments. There are no less than three 
distinct layers or sheets of this till or glacial clay. From the materials 
which compose this clay there is no doubt that the drift belongs to that 
accumulation of materials produced by the southwesterly movement of 
that great ice sheet whose centre of dispersion was somewhere near the 
height of land in the great peninsula of Labrador. These materials were 
derived from the great Archean complex, from the Laurentian and 
Huronian systems to the northeast, consisting mainly of granitoid 
gneisses and other crystalline aggregates, peculiar to those systems, and 
which are well developed throughout northern central Ontario, and the 
regions to the northeast of that province. Besides the Archean 
boulders present in this Labrador formation may be seen materials de- 
rived from the Bird’s Eye and Black River, Trenton, Utica and Lor- 
raine formations, which were picked up along the way and deposited at 
the time of the advance and retreat of the first ice sheet which had 
invaded this portion of Canada. The character of the materials which 
are seen in the second or middle boulder clay as well as in the upper, or 
third boulder clay sheets in and about Toronto differ but little in their 
constituents from those of the first or lowest boulder clay exposed, inas- 
much as the general trend and direction of the great ice sheet was 
