to be really indigenous to America. Now, with one exception, all the shells of both Upper and Lower Canada also inhabit the Atlantic region. The little group of fresh water bivalves, to which I endeavoured previously to draw some attention, forms this exception. Eight species of Cyclas and three of Pisidium are, so far as we know at present, peculiar to Canada, and have never been found elsewhere. But these little shells require to be carefully searched for, and are very similar one to an other; hence they may have been overlooked in the New England states.

When we turn to the sister science of botany, we shall find that somewhat different views of geographical distribution have been entertained. If we compare our knowledge of Canadian plants with Prof. Schouw's theories respecting the general geographical distribution of the vegetable kingdom we shall see that in Canada two botanical provinces meet. The first is the well-known Arctic flora, which is characterized by the abundance of mosses, Saxifrages, Gentians, species of Silene, Arenaria, and Dianthus; and also by the presence of many species of willow and sedges.

As defined by Prof. Schouw, the total absence of tropical families, a notable decrease of the forms peculiar to the temperate zone, and the prevalence of forests of firs and birches, form additional characteristics of this region. Geographically, it includes all the countries within the polar circle, with some parts of Europe, Asia and America to the south of it; as for example, the mountains of Scotland and Wales, Labrador, Greenland, and the northern part of Canada. Next we have what Prof. Schouw calls the region of Asters and Solidagos, characterized by the great variety of oaks and firs, the small number of Umbelliferæ and Cruciferæ, by the almost total absence of true heaths, which are here replaced by Vacciniums, and by the abundance of the said Asters and Solidagos. Geographically it includes Mr. Woodward's Atlantic region, and the southern part of Canada. Thus, judging from the distribution of Mollusca, Mr. Woodward thinks that Canada should rank as a distinct natural-history region, while on the contrary, judging from the evidence afforded by the vegetable kingdom,-according to Prof. Schouw's theory, part of Canada belongs to an Arctic, and part to an Atlantic region. But here again we must not neglect to inquire what light the geology throws upon this question, and turning to the geologic record, we shall find that since the first appearance of these animals and plants on the surface of our globe, great alterations in the relative distribution of land and water and a general subsi

dence and re-upheaval of the continents of Europe and America, have been effected. We shall do well to remember the brilliant generalizations of the late Edward Forbes, after a close study of the distribution of animals and plants in Great Britain, and of their connection with the tertiary deposits of the same country.

On the tops of the mountains near the lakes of Killarney, in the south of Ireland, occur a few plants, entirely different from those of the Scotch and Welsh mountains, but nearly agreeing with those of the Asturian mountains in the north of Spain. According to Forbes, the southern character of these Irish plants, and their extreme isolation, point to a period when a great mountain barrier extended across the Atlantic, uniting Ireland with Spain. Soon after this, arguing from similar data, he infers that another barrier connected the west of France with the south-west of England and thence to Ireland;-and a little later England and France were connected by dry land, towards the eastern part of the Channel. Upon this supposition it is easy to understand why two small snails (the Helix incarnata and Bithinia marginata,) which abound as Pleistocene fossils in the valley of the Thames, although extinct in Great Britain, are still found living in France.

At the time of the glacial drift, what are now the summits of the Scotch and Welsh mountains were then-Forbes argues-low islands, or members of chains of islands, extending to the area. of Norway, through a glacial sea-clothed with an Arctic vegetation, which in the gradual upheaval of those islands, and consequent change of climate, became limited to the summits of the new formed and still existing mountains. After this upheaval it is believed that Ireland was connected with England, and England with Germany, by vast plains, fragments of which still exist, and upon which lived the Irish elk, two-horned rhinoceri, the Arctic elephant (Elephas primigenius), and other quadrupeds now extinct, but which have left behind them in the gravels of our English drift, unmistakeable evidence of their having at one time roamed in great numbers over what is now Great Britain.

The array of facts which tends to corroborate Forbes's theories would occupy too much time to explain in detail;—I have merely stated his general views in so far as they affect the question at issue. Carrying out these well known generalizations, Sir Charles Lyell after visiting this country and studying the peculiar distribution of Pleistocene fossils in Lower Canada, published a theory which he thought would account for these phenomena. This

was that the land in North America, "after it had acquired its present outline of hill and valley, cliff and ravine," was subjected to a gradual submergence—and that at a subsequent period it re-emerged from the ocean. Again, it is a well-known fact, that more than half of the marine shells of the northern New England states, and also of the Gulf of the St. Lawrence are common to the seas of northern Europe. This has been held, with much probability, to prove the existence of a landway across the Atlantic since the epoch of the still living animals and plants.

It should be stated that many American shells, which are not now known to inhabit the European seas, occur fossil in the red crag of Great Britain-this would tend to prove the great antiquity of the existing fauna.

If too the Helix labyrinthica (a little snail common in Canada) be, as many of our best naturalists think, identical with a fossil species from the Eocene beds of the Isle of Wight, it is just possible that some of our land shells may prove to be even of still older date. It has been noticed by scientific men in Britain, that these fossil land shells from the Isle of Wight are of a group quite American in character. Neither should we forget the theory that at a period somewhat later geologically than these Eocene beds, the isthmus of Darien, or some portion of it at least, was submerged, and we should take into consideration the supposed consequent alteration of the currents of the gulf stream. It has been suggested that from this cause alone, the climate of Great Britain was then as cold as that of the island of Newfoundland at the present day.

But here in Canada, our knowledge of facts is much too meagre and unsatisfactory to enable us to generalize either on the distribution of plants and animals in British America, or on the connection between existing animals and the tertiary formations of this country. The deposits of land and fresh water shells in our lacustrine marls, require to be carefully worked out. and catalogues of the species which they contain to be published. In the living land and fresh water mollusca, much is yet to be done; -the neighbourhood of Lake Superior may yet produce many new fresh water forms, while the vicinity of Toronto, and that part of Canada to the south-west of Lake Erie are, conchologically speaking, almost unknown. The opening up of canals has caused a northward emigration of fresh water shells, and by this means several species have been enabled to travel from Ohio into the south-west peninsula of Canada. In my own private collection,

I have six fresh water shells hitherto not known to inhabit Canada, which have been introduced in this way; five are from the Welland Canal, and one is from the Thames river at Chatham, C.W.; they are all well-known Ohio shells. The object of this paper has been a suggestive one, and if by these few remarks I shall have attracted attention to the interesting subject of our land and fresh water shells, my labour will not have been in vain.

List of land and fresh water shells hitherto not known as inhabiting Lower Canada.

Anodonta undulata, Say. St. Charles River, near Quebec.
Anodonta decora, Lea. Old quarries near the Mile-end, Montreal.
Anodonta plana, Lea. Rideau Canal near Ottawa City.
Unio luteolus? Lam. var.

Quebec and Montreal.

Common in the St. Lawrence both at

Unio compressus, Lea. (U. alasmodontinus? Barnes). Assumption River, M. de Villeneuve: Rideau Canal near Ottawa City, Mr. Billings. Cyclas rhomboidea, Say; and two species as yet undetermined; St. Lawrence, at Quebec.

Pisidium variabile? Prime; and four species not yet determined. Planorbis armigerus, Say. Trenches in fields near Quebec. This shell belongs to the genus Planorbalina of Haldeman.

Planorbis deflectus, Say. Streams near Quebec.

Limnæa columella, Say. Common in the St. Lawrence near Quebec, at low water, with its variety macrostoma.

Helix rufescens, Muller.

probably introduced.

Common in the Cove fields, Quebec, but

Helix capsella, Gould. Island of Orleans, but very rare.
Helix dentifera, Binney. St. Lambert, Montreal.

Pupa armifera, Say. Abundant in the Cove fields, Quebec.
Pupa contracta, Say. Island of Orleans.

Shells new to Upper Canada.

From the Welland Canal and its neighbourhood:

Canadian fresh water shells which occur also on the west side of

Of these shells, two are not allowed to be good species; Limnæa catascopium being considered a variety of L. palustris, and Planorbis corpulentus of P. trivolvis, but in each case they form well marked varieties. My authority for their occurrence west of the Rocky Mountains is Dr. Binney, in his catalogue of the fluviatile gasteropoda of North America, published for the Smithsonian Institution, Washington.

REVIEWS AND NOTICES OF BOOKS.

Voyage d'André Michaux en Canada, depuis le lac Champlain jusqu'à la Baie d'Hudson.-By 0. Brunet, Professor of Botany at the Laval University. From the printing establishment of l'Abeille, Quebec; 8vo., 27 pages.

This is a notice of the voyages to North America of André Michaux, a native of France, made during the years 1785 to 1786; with a sketch of his life. The object of his travels was to make botanical researches and mark the locality of trees and plants peculiar to the country. He has rendered great service to science and deserves the especial consideration of Canadians, for he may be looked upon as the founder of Botany in Canada. The only work having any pretention to a history of Canadian plants which appeared before that of André Michaux was Cornuti's, published in 1635, under the title, Plantarum Canadensium Historia, which is far from being a complete flora, and it is besides defective in classification. Charlevoix gives a translation of this work into French, adding a number of plants which had subsequently been discovered. Kalm, the celebrated disciple of Linnæus and Professor of Natural History at Abo, had also visited America in 1749-51, at the request and charge of the King of Sweden; he extended his visit even to Canada, but the fruits his labours went to enrich the Species Plantarum of his great master, where to this day they are to be seen, being identified as his discoveries by the mark of the initial letter K. This would show that Canadian Botany may claim a respectable origin, as by this it is almost contemporaneous with the introduction of the science in modern times, botany owing its rational momenclature and classification to Linnæus. Michel Sarrazin, an inhabitant of Quebec and Physician to the King under the French dominion, and also a corresponding member of the Academy of Sciences, may be mentioned here as the first Canadian botanist, who became renowned for his discovery of the curious plant which bears his name-Sarracenia