916 REVIEWS 



the southern, having a length of thirty-two miles and an average 

 width of two miles, is the most important, though the others are not 

 without promise. F. D. Adams returned to his work in the pre- 

 Cambrian area of eastern Ontario. Two maps, covering about 4,200 

 square miles, have been prepared. The northern half of the area 

 is occupied by granite-gneiss (probably equivalent to Logan's 

 fundamental gneiss) while the rocks of the southern area are chiefly 

 ancient sediments, largely limestones, resting on the gneissic series, 

 but invaded, brecciated, and altered by it. Bathylithic masses of 

 gneiss occur in both the granite-gneiss and the ancient sedimentary 

 areas. In the southeastern portion of the area, associated with com- 

 paratively unaltered limestones, are masses of amphibolite and other 

 foliated rocks, with an occasional band of conglomerate. The nephe- 

 line syenite of the southern portion of the area seems to have some gen- 

 etic connection with the limestones and with the granites. Intrusions of 

 gabbro are found associated with the amphibolites. In southwestern 

 Ontario, R. Chalmers made a reconnaissance survey of the superficial 

 deposits, and has recorded some observations relative to recent changes 

 of the level of Lakes Huron and Erie. He also gathered data 

 bearing on the salt, oil, and gas industries of that part of the province. 

 In eastern Ontario R. W. Ells has made a re-survey of the Paleozoic 

 formations about Kingston with a view to determining the age of 

 certain limestones and shaly and arkose sandstones forming the basal 

 strata of the sedimentary series. Murray (Geological Survey of Canada, 

 1852-3) regarded the limestones as of Black River age and the sand- 

 stones as of Potsdam. The apparent conformity of the two led later 

 workers to suggest that the sandstones were a local development of 

 the Black River. Ells finds abundant proofs of the Black River age 

 of the limestones. As to the sandstones, though no conclusive proofs 

 were found, he inclines to the view of Murray. He gives brief notes 

 on the economic products of the area. Of these the more important 

 are iron, mica, feldspar, marl, and building-stone. The Survey has 

 planned the careful petrographical study of the rocks of the range of 

 volcanic hills which crosses the St. Lawrence valley in the vicinity of 

 Montreal. O. E. Le Roy has completed the work on Rigaud Mountain 

 and is at work on the rocks of Beloeil. Dr. Adams will soon publish 

 a description of Mount Johnson, and he and Professor Harrington are 

 at work on the petrography of Mount Royal. J. A. Dresser finds 

 Shefford Mountain to be composed of essexite, nordmarkite, and 

 pulaskite. Work on Anticosti island confirms the general features of 



