The Royal Society of Canada. 15 



formed. The folding of the coal-measures and of the succeeding 

 measures were referred to, and the opinion was advanced that com- 

 paratively little folding of the carboniferous had taken place in the 

 Lower Provinces since the close of the trias. During the carbonif- 

 erous period, in addition to the continental changes of level giving 

 rise to conditions of deposition characterizing the carboniferous 

 limestone, millstone-grit, etc., there were extensive foldings of a 

 more local character, apparently in some cases marking the closing 

 of these oscillations. These foldings and their subsequent denu- 

 dations have played an important part, hitherto but little studied 

 in modifying the conditions arising from the larger and more 

 extended movements which have hitherto principally received 

 attention, and show the district to have been far from quiet 

 during the carboniferous age. 



Professor R. Bell's paper on the causes of the fertility of the 

 land in the Canadian Northwest territories was of great interest. 

 The author, after referring to the various processes by which soils 

 in general are formed, pointed out the reason for the fertility or 

 otherwise of great districts in the older provinces. In the Cana- 

 dian Northwest a vast fertile tract stretches, with certain excep- 

 tions, from the Red River Valley to the Liard River, a distance 

 of some fourteen hundred miles. The soil of this tract was 

 characterized as a dark loam, of varying depth, and of a nearly 

 homogeneous consistency. The primary cause of the fertility of 

 this region was the abundance of the underlying crude material 

 out of which a finished soil could be made. This was derived 

 partly from the wide-spreading cretaceous marls, which were nearly 

 co-extensive with the fertile tract, and partly from the drift 

 during the glacial period. Dr. Bell next considered the process 

 by which the black loamy soil was formed out of this subsoil, and 

 he considered that the main agency was the work of moles and 

 other burrowing animals. Darwin had proved that in England 

 and some other countries earth-worms played the chief part in the 

 formation of the vegetable mould. These worms appeared to be 

 absent in the Northwest, owing principally to the frost penetrat- 

 ing into the ground beyond the depth to which worms can burrow, 

 but the moles and the ground-squirrels or gophers more than 

 make up for their absence. In the fertilized tracts the old and 

 new mole-hills cover the whole surface, rendering it hummocky, 

 which may be easily observed after the prairie has been swept by 



