914 REVIEWS 



Boundary Mining District of British Columbia. The rocks of the 

 district are largely eruptives and intrusives, consisting of greenstones, 

 granites, tuffs, and lava, though older sediments, consisting of lime- 

 stones, argillites, quartzites, and other metamorphic rocks have been 

 caught up and included in the igneous flows. The region is wholly 

 within the area covered by the Cordilleran ice sheet. The stria? 

 show that the movement was mainly S. 30 ° E. Assorted glacial 

 materials are very abundant, and terracing is very prominent, often 

 reaching a height of 2,000 feet above the present valley levels. The 

 ore bodies are of large size, but irregular in form and usually of low 

 grade. They occur in all rocks except the newest, and mineralization 

 has extended, with gradually decreasing richness, far into the country 

 rock. Deposits within the limestones or the greenstones and at the 

 contact of the two, are of most frequent occurrence. The vein 

 minerals are chiefly magnetite, pyrrhotite, chalcopyrite, marcasite, 

 arsenopyrite, and micaceous hematite, with more or less galena, 

 sphalerite, and molybdenite. Magnetite is never abundant where 

 pyrrhotite is prominent. The values are principally in copper, gold, 

 and silver. The smelters at Grand Forks and Greenwood have been 

 working steadily, but the pyritic smelter at Boundary Falls has not 

 yet been blown in. W. W. Leach continued the examination of the 

 Crow's Nest coal fields, which lie on the eastern border of British 

 Columbia. The main area covers about 230 square miles, has twenty- 

 two distinct seams with a total thickness of 216 feet, of which 100 feet 

 is workable coal of excellent quality. The smaller, or Green Hills 

 area, covers about seven square miles and contains 79 feet of workable 

 coal in seven seams. L. M. Lambe resumed his work on the Creta- 

 ceous rocks of the Red Deer River, Alberta, and succeeded " in securing 

 a large collection of chelonian, dinosaurian, crocodilian, fish, primitive 

 mammalian, and other vertebrate remains of considerable value." 

 Two Chelonians — Trionyx foveatus and Trionyx vagans — are figured 

 and described. William Mclnnes worked on the pre-Cambrian for- 

 mations between Lakes Superior and Manitoba. " The primary object 

 of the season's work was to trace with greater accuracy the Sturgeon 

 Lake gold-bearing belt and to work out the geology of an area lying 

 to the southeast of the eastern half of Lac Seul." All of the impor- 

 tant Huronian areas of this region are now mapped. Some promising 

 mineral lands are being developed. A. W. G. Wilson spent the 

 summer in the region west of the Nipigon river and lake. The rocks 

 of the area studied belong to the Laurentian, Huronian, and Animikie 



