180 THE CANADIAN NATURALIST. [Vol. 



VI. 



the boreal forms altogether disappearing. For a very full exhi- 

 bition of these facts, I may refer to Dr. Packard's paper. 



The stratified sand and gravel of Nova Scotia rests upon and 

 is newer than the Boulder-clay, and is also newer than the strati- 

 fied marine clays above referred to. Its age is probably that of 

 the Saxicava Sand of the St. Lawrence valley. The former rela- 

 tion may often be seen in coast sections or river banks, and occa- 

 sionally in road cuttings. I observed some years ago an instruc- 

 tive illustration of this fact, in a bank on the shore a little to the 

 Eastward of Merigomish harbour. At this place the lower part 

 of the bank consists of clay and sand with angular stones, prin- 

 cipally sandstones. Upon this rests a bed of fine sand and small 

 rounded gravel with layers of coarser pebbles. The gravel is 

 separated from the drift below by a layer of the same sort of an- 

 gular stones that appear in the drift, showing that the currents 

 which deposited the upper bed have washed away some of the 

 finer portions of the drift before the sand and gravel were thrown 

 down. In this section, as well as in most others that I have ex- 

 amined, the lower part of the stratified gravel is finer than the 

 upper part, and contains more sand. 



In some cases we can trace the pebbles of the gravels to ancient 

 conglomerate rocks which have furnished them by their decay; 

 but in other instances the pebbles may have been rounded by the 

 waters that deposited them in their present place. In places, 

 however, where old pebble rocks do not occur, we sometimes find, 

 instead of gravel, beds of fine laminated sand. A very remark- 

 able instance of the connexion of superficial gravels with ancient 

 pebble rocks occurs in the county of Pictou. In the coal forma- 

 tion of this count}^ there occurs a very thick bed of conglomerate, 

 the outcrop of which, owing to its comparative hardness and great 

 mass, forms a high ridge extending from the hill behind New 

 Glasgow across the East and Middle Rivers, and along the South 

 of the West River, and then, crossing the West River, re-appears 

 in Rogers' Hill. The valleys of these three rivers have been 

 cut through this bed, and the material thus removed has been 

 heaped up in hillocks and beds of gravel, along the banks of the 

 streams, on the side toward which the water now flows, which 

 happens to be the North and North-east. Accordingly, along the 

 course of the Albion Mines Railway and the lower parts of the 

 Middle and West Rivers, these gravel beds are everywhere exposed 

 in the road-cuttings, and may in some places be seen to rest on 



