98 



Canadian Record of Science. 



to have been found embedded in clay in the region between 

 Irvine and the Cypress Hills in the Xorth-West. They 

 consist of a greyish-white, opalescent chalcedony with hard- 

 ness of 7 and specific gravity 2"592. The person wbo found 

 them supposed they were fossils, and some of them certainly 

 remind one of nummulites. In some cases they are flat on 

 both sides, in others flat on one side and convex on the other. 

 The convex sides are mostly smooth, and in some cases 

 exhibit slight radial depressions or furrows. The flat sides, 

 however, show marked concentric furrows. When viewed 

 by transmitted light, the concretions are seen to have a 

 radiated as well as a concentric structure, and the radiated 

 structure is made much more apparent by grinding down 



until the concretion has become transparent. This is 

 especially true if the section be examined in polarised light 

 when it is also seen to be doubly refracting. The concretions 

 are from a-quarter of an inch or less in diameter up to 



