15 



sand was evidently deposited in shallow water where oxida- 

 tion was taking place, since some of the coarser beds of 

 gravelly sand in the section are cemented with limonite. 



Bluish gray finely laminated clay, overlying the Don 

 beds conformably to a thickness of from 7 to 22 feet, was 

 laid down in much deeper water, and shows no fossils ex- 

 cept a little peaty matter. It represents the lowest part of 

 the Scarboro beds. 



A thin sheet of boulder clay, the second in order, rests 

 upon the eroded surface of the stratified clay just mentioned, 

 followed by 80 feet of rather coarsely laminated clay some- 

 times containing subangular striated stones. The source 

 from which this clay was derived must have been the ice 

 margin not many miles away. The lower stratified clay, 

 which is interglacial, is formed of well leached material 

 and burns to red brick ; while the overlying stratified clay 

 is so strongly charged with lime as to burn to a buff brick. 



The top of the section consists of a few feet of brown 

 sand and loam with large boulders, resulting from the wave 

 work of lake Iroquois. The stones have evidently been 

 washed out of an overlying sheet of till, which may still 

 be seen in the old shore cliff half a mile to the north. 



The lower 25 feet of Don interglacial beds are crowded 

 with fossils and form the most important part of the sec- 

 tion. From them wood or leaves of thirty-two species of 

 trees have been obtained and forty-one species of shell-fish, 

 of which twelve are unios or anodons, in addition to un- 

 determined beetles, cyprids, etc. 



The following list of interglacial plants was supplied 

 by the late Professor Penhallow : — 



Acer pleistocenicum. 



" spicatum. 



" torontoniensis. 

 Asimima triloba. 

 Carya alba. 



ChamcEcyparis sphccroidea. 

 Clethra alnifolia. 

 Crategus punctata. 

 Cyperacece sp. 

 *Drepanocladus capillifolius. 



*Determined by Mr. A. J. Grout. 



