the boreal forms altogether disappearing. For a very full exhibition of these facts, I may refer to Dr. Packard's paper.

The stratified sand and gravel of Nova Scotia rests upon and is newer than the Boulder-clay, and is also newer than the stratified marine clays above referred to. Its age is probably that of the Saxicava Sand of the St. Lawrence valley. The former relation may often be seen in coast sections or river banks, and occasionally in road cuttings. I observed some years ago an instructive illustration of this fact, in a bank on the shore a little to the Eastward of Merigomish harbour. At this place the lower part of the bank consists of clay and sand with angular stones, principally sandstones. Upon this rests a bed of fine sand and small rounded gravel with layers of coarser pebbles. The gravel is separated from the drift below by a layer of the same sort of angular stones that appear in the drift, showing that the currents which deposited the upper bed have washed away some of the finer portions of the drift before the sand and gravel were thrown down. In this section, as well as in most others that I have examined, the lower part of the stratified gravel is finer than the upper part, and contains more sand.

In some cases we can trace the pebbles of the gravels to ancient conglomerate rocks which have furnished them by their decay; but in other instances the pebbles may have been rounded by the waters that deposited them in their present place. In places, however, where old pebble rocks do not occur, we sometimes find, instead of gravel, beds of fine laminated sand. A very remarkable instance of the connexion of superficial gravels with ancient pebble rocks occurs in the county of Pictou. In the coal formation of this county there occurs a very thick bed of conglomerate, the outcrop of which, owing to its comparative hardness and great mass, forms a high ridge extending from the hill behind New Glasgow across the East and Middle Rivers, and along the South of the West River, and then, crossing the West River, re-appears in Rogers' Hill. The valleys of these three rivers have been cut through this bed, and the material thus removed has been heaped up in hillocks and beds of gravel, along the banks of the streams, on the side toward which the water now flows, which happens to be the North and North-east. Accordingly, along the course of the Albion Mines Railway and the lower parts of the Middle and West Rivers, these gravel beds are everywhere exposed in the road-cuttings, and may in some places be seen to rest on

the Boulder clay, showing that the cutting of these valleys was completed after the drift was produced. Similar instances of the connexion of gravel with conglomerate occur near Antigonish, and on the sides of the Cobequid mountains, where some of the valleys have at their Southern entrances immense tongues of gravel extending out into the plain, as if currents of enormous volume had swept through them from North to South.

The stratified gravels do not, like the older drift, form a continuous sheet spreading over the surface. They occur in mounds and long ridges, or eskers, sometimes extending for miles over the country. One of the most remarkable of these ridges is the "Boar's Back," which runs along the West side of the Hebert River in Cumberland. It is a narrow ridge, perhaps from ten to twenty feet in height, and cut across in several places by the channels of small brooks. The ground on either side appears low and flat. For eight miles it forms a natural road, rough indeed, but practicable with care to a carriage, the general direction being nearly North and South. What its extent or course may be beyond the points where the road enters on and leaves it, I do not know; but it appears to extend from the base of the Cobequid mountains to a ridge of sandstone that crosses the lower part of the Hebert river. It consists of gravel and sand, whether stratified or not I could not ascertain, with a few large boulders. Another very singular ridge of this kind is that running along the West side of Clyde river in Shelburne county. This ridge is higher than that on Hebert river, but, like it, extends parallel to the river, and forms a natural road, improved by art in such a manner as to be a very tolerable highway. Along a great part of its course it is separated from the river by a low alluvial flat, and on the land side a swamp intervenes between it and the higher ground. Shorter and more interrupted ridges of this kind may also be seen in the country Northward and Eastward of the town of Pictou. In sections they are seen to be stratified, and they generally occur on low or level tracts, and in places where if the country were submerged, the surf or marine currents and tides might be expected to throw up ridges. The presence of boulders shows that ice grounded on these ridges, and it, probably by its pressure, in some instances, modified their forms. These eskers, or "horse-backs," must not, however, be confounded with glacier moraines, to which in structure they bear no resemblance what

ever.

D*

It is probably to this more modern part of the Post-pliocene, if not to a more recent period following the elevation of the land, that the bones of the mastodon found in Cape Breton, and described in "Acadian Geology," belong.

For many additional facts relating to the Post-pliocene of New Brunswick, I may refer to the valuable paper by Mr. Matthew, already mentioned.

4. Lower St. Lawrence-North Side.

Descriptions of the Post-pliocene deposits of this region are contained in several of my papers above cited, but I shall here give a summary of these, with the corrections and additional facts obtained within the past few years.

Saguenay River.-I have already, in part first, referred to the glacial striation of this region, and perhaps no better example could be found of those lateral valleys along which ice seems to have been poured into the St. Lawrence from the North. The gorge of the Saguenay is a narrow and deep cut, running nearly N.W. and S.E., or at right angles to the course of the St. Lawrence, and of the Laurentian ridges. It extends inland more than forty-five miles, and then divides into two branches, one of which is occupied by the continuation of the river to Lake St. John, the other by Ha-Ha Bay and a valley at its head. In the lower part of its course, as far as Ha-Ha Bay, this gorge is from 50 to 140 fathoms deep, below the level of the tide in the St. Lawrence, and in some places the cliffs on its banks rise abruptly to 1500 feet above the water level, so that its extreme depth is nearly 2400 feet, while its width varies from about a mile to a mile and ahalf. The striated surfaces and the roches moutonnées seen in this gorge and on the hills on its sides, to a height of at least 300 feet, shew that in the glacial period a powerful stream of ice must have flowed down this gorge into the St. Lawrence, though whether it was occupied by a glacier or constituted a fiord leading from one, like many in Greenland, or was a strait traversed by bergs, does not appear. Possibly, with different levels of the land, these conditions may have alternated. I cannot imagine anything more like what the Saguenay may have been at this time, than the view of Franz Joseph Fiord in East Greenland, brought home by the second German expedition to that country, in the present year, and which, with other discoveries of that

Copied in the "Leisure Hour" for November, 1871.

expedition soon to be published by Dr. Petermann, will go far to remove the prevailing error as to Greenland being covered with a universal glacier; whereas it seems to be a rocky and mostly snow-clad country, with very large glaciers in its valleys.

The strikes of the gneiss on the opposite sides of the Saguenay indicate that it occupies a line of transverse fracture, constituting a weak portion of the Laurentian ridges, and this has evidently been smoothed and deepened by water and ice under conditions different from the present, in which it is probable that the channel is being gradually filled with mud. Its excavation must have taken place before the deposition of the thick beds of marine clay (Leda clay) which appear near its mouth and in its tributaries, sometimes passing into Boulder-clay below, and capped by sand and gravel. It is indeed not improbable that in the later Post-pliocene it was in great part filled up with such deposits, which have been swept away in the course of the re-elevation of the land.

At Tadoussac, at the mouth of the Saguenay, where the underlying formation is the Laurentian gneiss, the Post-pliocene beds attain to great thickness, but are of simple structure and slightly fossiliferous. The principal part is a stratified sandy clay with few boulders, except in places near the ridges of Laurentian rocks, when it becomes filled with numerous rounded blocks and pebbles of gneiss. This forms high banks eastward of Tadoussac. It contains a few shells of Tellina Grænlandica and Leda truncata, and a little inland, at Bergeron River, it also contains Cardium Islandicum, Astarte elliptica, and Rhynchonella psittacea. It resembles some of the beds seen on the South side of the river St. Lawrence, and has also much of the aspect of the Leda clay, as developed in the valley of the Ottawa. On this clay there rest in places thick beds of yellow sand and gravel.

At Tadoussac these deposits have been cut into a succession of terraces which are well seen near the hotel and old church. The lowest, near the shore, is about ten feet high; the second, on which the hotel stands, is forty feet; the third is 120 to 150 feet in height, and is uneven at top. The highest, which consists of sand and gravel, is about 250 feet in height. Above this the country inland consists of bare Laurentian rocks. have been cut out of deposits, once more extensive, in the process of elevation of the land; and the present flats off the mouth of the Saguenay, would form a similar terrace as wide as any of the others, if the country were to experience another elevatory move

These terraces

ment. On the third terrace I observed a few large Laurentiau boulders, and some pieces of red and gray shale of the Quebec group, indicating the action of coast-ice when this terrace was cut. On the highest terrace there were also a few boulders; and both terraces are capped with pebbly sand and well rounded gravel, indicating the long-continued action of the waves at the levels which they represent.

Murray Bay, &c.-At Murray Bay, Petit Mal Bay, and Les Eboulements, as noticed above, the system of Post-pliocene terraces is well developed. On the West side of Murray Bay, the Silurian rocks of White Point, immediately within the pier, form a steep cliff, in the middle of which is a terraced step marking an ancient sea level. At the end nearest the pier the sea has again cut back to the old cliff, leaving merely a narrow shelf; but toward the inner side this shelf rapidly expands into the sandy flat along which the main road runs, and which is continuous with the lower plain extending all the way to the head of the bay. In this flat the upper portion of the Post-pliocene deposit seems to consist principally of sand and gravel, resting on stony clay. In the former, which corresponds to the Saxicava sand of Montreal, I found only a few valves of Tellica Groenlandica which is still the most abundant shell on the modern beach. In the latter, corresponding to the Leda clay, which is best seen in some parts of the shore at low tide, I found a number of deep water shells of the following species, all of which, except Spirorbis spirillum and Aphrodite Grænlandica, have been found in these deposits at Quebec and Montreal.

Fusus tornatus.

Trophon Scalariforme.
Margarita helicina.
Cylichna occulta.

Pecten Islandicus.

Tellina calcarea.

Leda truncata.

Saxicava rugosa.
Aphrodite Grænlandica.

Mytilus edulis.

Mya arenaria.

Balanus Hameri.
Spirorbis spirillum.
S. vitrea.

Serpula vermicularis.