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 CANADA

geography]

minerals of less intrinsic value, will all in the near future be likewise utilized. Turning back to the general physiographical features and geological history of Canada as a whole, after the above review of its several districts, it will be observed that the Laurentian plateau, with its surrounding areas of old rocks in the east, may be regarded broadly as constituting an area of which the history extends to the end of the Palaeozoic era, since which it has remained comparatively unaffected by orographic movements and relatively stable. This great region stretches westwards to Manitoba and the south-western edge of the Laurentian plateau along its course to the Arctic Ocean. From this dividing line the Cretaceous and Tertiary formations become important and widespread. During the early stages of these later times the sea, extending from the Pacific side, Year. 1894 1895 1896 1897 1898

Ontario. Rain. Snow In. In. 23-30 55-1 20-65 81-4 22-36 73-3 28-31 73-0 30-14 89-8

Quebec. Rain. Snow, In. In. 22-39 84-8 25-09 93-0 124-0 2528-09 91-4 105-3 26-

Nova Scotia. Rain. Snow, In. In. 29-31 80-3 36-71 75-1 36-88 64-8 38-94 86-5 44-46 89-0

529

covered much of what is now the western part of the continent, from which it was gradually excluded by recurrent movements of elevation and mountain-making that did not affect the already stable eastern half of the continent. (g. m. d.) Climate.—It is misleading to speak of the climate as a whole for there are many climates. Not only do the several provinces and territories differ materially, but there are great variations according to locality within most of the provinces themselves. But it may be said, in a general way, that the climates in the neighbourhood of the oceans are milder and damper than in the interior, and that the western or sea-coast portion of British Columbia is milder and damper than the maritime provinces of the Atlantic. Throughout the greater part there are extremes of temperature in winter and summer, but in summer the nights are cool and in winter the atmosphere is dry, bracing, and healthy. The rain and snowfall of the several provinces are shown for five years in the following table :—

New Brunswick. P. E. Island. Manitoba. British Columbia. N. W. Territories. Rain. Snow. Rain. Snow. Rain. Snow, Rain. Snow. Rain. Snow, In. In. In. In. In. In. In. In. In. 23-74 103-3 10-58 12-62 47-9 41-92 70-4 9-24 41-7 3114-64 44 "4 3 88-9 99-6 3567-0 10-54 31-3 25-56 91-1 56-7 16-00 62-9 3668 58-5 1060-3 33-76 80-3 56-4 9-66 59-1 41-10 42-6 1153-2 32112-0 65-4 16-75 53-8 2 43-89 26-2 10-29 52-4 47

Note.—The articles on the several provinces should be consulted for close information as to climate. The case of British Columbia may be cited to show the need for this. The rain and snowfall for this province show an average of about 41 inches of rain and 53 of snow, yet in one large division of the province it may be said to rain during nearly every day in the winter, there being hardly a week of snow, while at the same time a division of many million acres is dependent on irrigation for raising its crops. Tides.—The tides of the Atlantic and Pacific coasts, with the currents dependent upon them, possess a special importance in connexion with the navigation of the St Lawrence, which forms the main commercial avenue from the east. Of late years a systematic investigation of the tides and currents has been undertaken by the Canadian Government. The tides of the St Lawrence enter the Gulf from the Atlantic chiefly through Cabot Strait, between Cape Breton and Newfoundland, which has a width of 75 miles and a depth of 250 fathoms. The tide entering through Belle Isle Strait (12 miles wide and 30 fathoms deep) is comparatively little felt. The tide so expands in the Gulf of St Lawrence as to become almost inappreciable in places, and the greatest range is attained in Northumberland Strait and at the head of Chaleurs Bay, where it amounts to about 9 feet. At the entrance to the St Lawrence at Anticosti, it has again the oceanic range of some 6 feet, and it proceeds up the estuary with an ever-increasing range which attains its maximum of 19 feet at the lower end of Orleans Island, at 650 miles from the ocean at Cabot Strait. This must he considered as the true head of the estuary. At Quebec, 30 miles farther up, the range is nearly as great, but at 40 miles above Quebec it is largely cut off by the Richelieu rapids, and finally ceases to be felt at Three Rivers, at the lower end of Lake St Peter. On the Pacific coast the two tides of the same day are very unequal, so much so that for a month at a time there is practically only one high water and one low water during the twenty-four hours. This feature of the tide occurs widely on the western coast of America. In the Bay of Fundy the height of the tide while quite exceptional has been much exaggerated. From careful measurements made daily for four months by the engineeis of the Chignecto Ship Railway, the extreme range in Cumberland basin at the head of the bay was 49-00 feet, and the average spring range was 42-21 feet. From the lowest level of low water then observed, to the level of the highest tide ever known, which flooded the country on 5th October 1869, during a severe storm, the greatest difference of level in Cumberland basin is 53 feet. At Noel Bay, near the head of the other arm of the Bay of Fundy, the range of ordinary spring tides as stated in the Admiralty charts is 50^ feet. A noteworthy tidal bore occurs at Moncton on the Petitcodiac river, at the extreme head of the Bay of Fundy. Attention has also been given to the establishment of the mean sea-level at a number of places and its reference to permanent marks. A case of special interest occurs in comparing the mean levels on opposite sides of the Chignecto Isthmus, with a range of nearly 50 feet on one side and only 8 feet on the other. Flora. —The general flora of the Maritime Provinces, Quebec and Eastern Ontario is much the same, except that in Nova Scotia a number of species are found common also to Newftrandland that

are not apparent inland. Professor Macoun gives us a few notable species—Calluna vulgaris, Salisb., Alchemilla vulgaris, L., Rhododendron maximum, L., Ilex glabia, Gray, Hudsonia ericoidcs, L., Gaylussacia dumosa, F. and G., and Schezcea pusilla, Pursh. In New Brunswick the western flora begins to appear as well as immigrants from the south, while in the next eastern province, Quebec, the flora varies considerably. In the lower St Lawrence country and about the Gulf many Arctic and sub-Arctic species are found. On the shores of the lower reaches Thalictrum alpinum, L., Vesicaria arctica, Richards, Arapis alpina, L., Saxifraga oppositifolia, L., Cerastium alpinum, L., Saxifraga ccespitosa, L. and S. have been gathered, and on the Shickshock Mountains of Eastern Canada Silene acaulis, L., Lychnis alpina, L., Cassiope hypnoides, Don., Rhododendron laponicum, Wahl, and many others. On the summit of these hills (4000 feet) have been collected Aspidium aculeatum, Swartz var., Scopxdinum, D. C. Eaton, Pellcea densa, Hook, Gallium kamtschaticum, Sletten. From the city of Quebec westwards there is a constantly increasing ratio of southern forms, and when the mountain (so called) at Montreal is reached the representative Ontario flora begins. In Ontario the flora of the northern part is much the same as that of the Gulf of St Lawrence, but from Montreal along the Ottawa and St Lawrence valleys the flora takes a more southern aspect, and trees, shrubs, and herbaceous plants not found in the eastern parts of the Dominion become common. In the forest regions north of the lakes the vegetation on the shores of Lake Erie requires a high winter temperature, while the east and north shores of Lake Superior have a boreal vegetation that shows the summer temperature of this enormous water-stretch to be quite low. Beyond the forest country of Ontario come the prairies of Manitoba and the North-West Territories. In the ravines the eastern flora continues for some distance, and then disappearing gives place to that of the prairie, which is found everywhere between the Red River and the Rocky Mountains except in wooded and damp localities. Northwards, in the Saskatchewan country, the flora of the forest and that of the prairies intermingle. On the prairies and the foot-hills of the Rocky Mountains a great variety of grasses are found, several years’ collection resulting in 42 genera and 156 species. Of the best hay and pasture grasses, Agropyrum elymus, Stipa, Bromus, Agrostis, Calamagrostes and Poa, there are 59 species. Besides the grasses there are leguminous plants valuable for pasture — Astragalus, Vicia (wild vetch), Lathyrus (wild pea) of which there are many species. The rose family is represented by Prunus, Potentilla, Fragaria, Rosa, Rubus, and Amelanchier. About the saline lakes and marshes of the prairie country are found Ruppiamaritima, L., Heliotropium curassavicum, L., natives of the Atlantic coast, and numerous species of Chenopodium, Atriplex, and allied genera. The flora of the forest belt of the North - West Territories differs little from that of Northern Ontario. At the beginning of the elevation of the Rocky Mountains there is a luxurious growth of herbaceous plants, including a number of rare umbellifers. At the higher levels the vegetation becomes more Arctic. Northwards the valleys of the Peace and other rivers differ little from those of Quebec and the northern prairies. On the western slope of the mountains, that is the Selkirk and Coast S. II. — 67