322 ROYAL SOCIETY OF CANADA 



occupy a trough between ridges of two earlier igneous roclis and tlie 

 latter, alone of the rocks of the district, may possibly be of pre- 

 Cambrian Age. 



(12). Ells, R. W. — The article outlines the results of various geological investiga- 

 tions at a number of localities within the province. 



(13) Evans, H. F. — ^"A reconnaissance into Highland Valley, British Columbia." 



Mining World, Vol. 22, pp. 520-527, and p. 546; 1905. 



The area known a^ the interior plateau of British Columbia wae, 

 during early Tertiary, denuded to base level, has since passed through 

 a succession of elevations and depressions, has been at times an area 

 of deposition and a theatre of volcanic eruptions. 



(13a) Evans, H. F. — " In the Eocene Tertiary the interior plateau was reduced 

 by prolonged denudation to the conditions of an approximately uniform 

 plane. Since then, the area has been defonned by earth movements, 

 strata have been deposited and volcanic flows have taken place. 



(14) Evans, H. F. — The two articles contain a summary description of the occur- 



rence of molybdenum in a system of quartz veins cutting a granite. 



(15) Gilpin, B. J. — The article contains a number of hitherto unpublished, 



sections and analyses of coals of the province. 



(16) HOTCHKiss, W. O. — The geological formation of the district, in ascending 



order, are, Keewatin, Laurentian, Lower Huronian, Middle Huronian, 

 large masses of diabase probably of Keweenawan age, and Niagara 

 limestone. The Keewatin greenstone schists are intruded by the Lau- 

 rentian granite and both are overlain by the Lower Huronian which 

 is composed of conglomerates and shales, usually lying in a nearly 

 horizontal position. The ores occur in narrow, vertical fissures in the 

 Lower Huronian near the contact with the Keewatin and usually also 

 near the diabase. The principal gangue mineral is calcite with acces- 

 sory quartite. The most valuable mineral is native silver, the most 

 abundant, smaltite chloanthite while of the many accessory minerals, 

 those mined for values are chiefly niccolite cobalite. The Keewatin 

 schists are well mineralized with arsenical iron and copper pyrite. 

 The deposits are possibly due to meteoric waters which, warmed by 

 the presence of the (slowly cooling masses of diabase, derived the ores, 

 to a large extent, form the Keewatin scists. The cobalt ores and 

 calcite were first deposited and, after a second period of fracturing, 

 the silver was deposited, the cobalt ores acting as a precipitating agent 

 for the silver. 



(17) Low, A. P. — A summary of the results of the expedition, including notes 



on the geology of the regions visited. 



(18) MclNNES, Wm. — A summary description of the season's work. The region 



visifted is one of low relief and owes its most striking features to 

 deposits of glacial origin. The underlying rocks are all Archean, mainly 

 biotite gneisses with areas of Keewatin schists. 



