3 Laboratory work, in addition to that done in the offices of the Geological Survey, was carried out at the University of British Columbia and at Princeton University. The writer appreciates the advice and criticisms received from the faculty of these institutions, particularly Professors H. C. Gunning and K. DeP. Watson of the University of British Columbia and Professors A. F. Buddington, H. H. Hess, and B. F. Howell of Princeton University. For examination of fossil collections in addition to that done by the officers of the Paleontological Division of the Geological Survey of Canada, the writer is especially indebted to Professor V. J. Okulitch of the University of British Columbia and Professor B. F. Howell of Princeton University; Professor E. C. Stumm of the University of Michigan, Professor M. A. Fritz of the University of Toronto, and Dr. T. H. Withers of the British Museum also kindly examined material. The writer’s field assistants J. O. Wheeler and W. H. Dow also assisted with mineralographic investigations. Lastly, the writer would like to express his indebtedness to Dr. J. E. Armstrong of the Geological Survey, under whose direction he worked in 1945, and upon whose knowledge of the geology of the surrounding areas he has drawn freely. BIBLIOGRAPHY Adams, F. D. (1909): On the origin of the Amphibolites of the Laurentian Area; Jour. Geol., vol. 17, pp. 1-18. Armstrong, J. E. (1941): Fort Fraser, West Half; Geol. Surv., Canada, Map 631A. (1944): Northern Part of the Pinchi Lake Mercury Belt, British Columbia; Geol. Surv., Canada, Paper 44-5. (1946a): Aiken Lake (South Half), British Columbia; Geol. Surv., Canada, Paper 46-11. (1946b): Takla, Cassiar District, British Columbia; Geol. Surv., Canada, Map 844A (descriptive notes). (1947) : Fort St. James, British Columbia (geological map) ; Geol. Surv., Canada, p 907A. (1949): Fort St. James Map-area, British Columbia; Geol. Surv., Canada, Mem. 252. Armstrong, J. E., and Roots, E. F. (1948): Aiken Lake Map-area, British Columbia; Geol. Surv., Canada, Paper 48-5. aw Armstrong, J. E., and Thurber, J. B. (1945): Manson Creek Map-area, British Columbia; Geol. Surv., Canada, Paper 45-9. se Armstrong, J. E., Tipper, H. W., and Hoadley, J. W. (1947): Carp Lake, British Columbia; Geol. Surv., Canada, Paper 47-13. } Armstrong, J. E., and Tipper, H. W. (1948): Glaciation in North-Central British Columbia; Amer. Jour. Sci., vol. 246, pp. 283-310. ; Barrow, G. (1912): On the Geology of Lower Dee-side and the Southern Highland Border; Geol. Assoc. Proc., vol. xxiii, pp. 268-284. Barth, T. F. W. (1928): Zur Genesis der Pegmatite im Urgebirge; Chemie der Erde, 1928, pp. 95-134. (1930): Om Oprinnelsen Au Enkelte Grunnfjellsamfiboliter I Agder; Norsk Geol. Tidsskrift, vol. 11, p. 219. Behre, C. H., Jr. (1933): Talus Behavior Above Timber in the Rocky Mountains; Jour. Geol., vol. 41, pp. 622-814. Bostock, H. S. (1948): Physiography of the Canadian Cordillera, with Special Reference to the Area North of the Fifty-fifth Parallel; Geol. Surv., Canada, Mem. 247. Bowen, N. L. (1917): The Problem of the Anorthosites; Jour. Geol., vol. 25, pp. 209-243. (1928): The Evolution of the Igneous Rocks; Princeton University Press, 1928. Bowen, N. L., and Tuttle, O. F. (1949): The System MgO-Si0e2-H20; Bull. Geol. Soc. Amer., vol. 60, pp. 489-460.