Petroleum is produced in Canada in New Brunswick, Ontario, North-West Territories, and in Alberta. Recently a new oilfield has been opened up on the Alberta-Saskatchewan boundary at Lloydminster. Prospecting at the present time is also being undertaken in Gaspe Peninsula of Quebec and in the Peace River Block of British Columbia.

The Permian fish-fauna of England has been studied by the present writer since 1932. In 1933 Dr. H. Aldinger, then working in Professor E. A. Stensiö's laboratory in Stockholm, informed me of the constitution of a fish-fauna from East Greenland which he was studying. The resemblances to the Marl Slate fishes were remarkable, and I found it extremely difficult, and in some cases impossible, to separate certain forms found in the two areas.

The helium method of determining the ages of fine-grained basic igneous rocks has now been so far developed as to be applicable to various geological and petrological problems, particularly where geological periods are involved, as in the problem here discussed. For details of the history of this development up to the beginning of 1937 reference may be made to Holmes, 1931; Urry, 1933; Lane and Urry, 1935; Urry, 1936 (b); Holmes and Paneth, 1936; and Holmes, 1937. During 1937 it was found that many of the helium-ratios on which the ‘helium’ time-scale had been based were too high, because of a previously unsuspected error in radium determination due to reliance having being placed on a radium standard which was seriously at fault. To clear up this embarrassing situation an immediate effort was made by several investigators in collaboration, and the first fruits of their work have recently become available (Evans, Goodman, Keevil, Lane, and Urry, 1939).

The nature and arrangement of the “gills” of Eurypterids is not known in detail. A specimen of Slimonia in the Sedgwick Museum (No. A16237a), figured by Laurie (1893, pl. 1, figs. 5, 6, p. 514), seems to show their structure and segmental arrangement better than any described elsewhere. Owing to the rather poor quality of Laurie's figure and to the important conclusions which follow a study of this specimen, it has been thought fit to re-describe it here.

As a result of recent work on the correlation of the Coal Measures in the various British coalfields it is now possible to determine the relative ages of the chief productive measures in the different areas. Some aspects of this work were summarized in 1933 but much further work has been done since that time, especially with reference to the Scottish coalfields (Weir and Leitch, 1936). The results of these investigations may be expected to throw considerable light on the physiography and other factors controlling the deposition of the Upper Carboniferous rocks, but in the present note attention is drawn only to the zonal distribution of the more important coals in various British coalfields.