of these can be approached on foot at low water, and the rest are only separated by shallow channels. On going round the coast I began to notice that the peat banks formed frequently the sea-margin at high water; and feeling that it was a point of some geological importance, I noted the places on my sketch of the coast, till at last finding that the phenomenon was extremely common, occurring perhaps twenty times in a day's walk, it was no longer necessary to record its occurrence. After examining hundreds of examples, I came to the conclusion that, in these instances, there was no other way of accounting for peat banks having that position with regard to the sea-margin, than by the subsidence of the land. In many of the cases referred to, the peat rests at once upon the naked gneiss. Now, the surface of the gneiss is as rugged as, and not very unlike what, the surface of the ocean would be if it were suddenly solidified in the middle of a violent storm. The peat has grown over the undulatory surface, but, as was to be expected, is deepest in the depressions, where I have sometimes seen it in section more than ten feet in height. Let it be supposed that the relative levels of land and sea remained the same until the formation of peat had occurred, and then that the land began to subside. The effect would be that when the sea reached the foot of the peat banks small cliffs would form, identical in their features with those of clay or gravel, or any other soft material. But from the extreme softness of the peat the sea would quickly eat it away, and work itself into all the sinuosities of the surface gneiss that were below the level of high water. This is what has happened around Benbecula; the sea at high water flowing in amongst the knolls, at first forming a simple gap, then branching out like the arms of a tree; at a further stage in the destruction of the peat, a group of islands is formed, till at last the whole vegetable soil is washed away, and a few bare rocks serve to point out where but one generation ago the cattle have pastured and corn has grown. Some of these rocks, which are now completely bare, still bear the names of particular plants that once grew upon them. It is difficult in words to convey an idea of the appearances and of the facts; but an inspection of the coast would show that the peat could only have been brought into

its present position by the subsidence of the land. There are, indeed, but two other ways by which the peat can be found to form the sea-coast; one is by the action of the sea upon the shore, the other by the peat advancing to the sea by slip. But neither of these cases will apply to the sea threading in among the knolls and hillocks, eating out holes at first, which become pools, then lagunes, till at last the land that enclosed them is all gone. It must therefore be accepted as a fact, that the land has subsided (and is subsiding) since the peat began to form, and, consequently, that the stone circles of the Lewis are of an age anterior to that subsidence; it follows, then, that if the rate and quantity of subsidence were known, and supposing it to be uniform, we should arrive at the least age of the Pagan monuments.

Although we cannot arrive at the whole quantity, we have fortunately a measure of a part of that subsidence; this is afforded by what have foolishly been called submarine forests, but which are in fact submerged peat-banks.

In the Orkneys I have noted six places at which submarine peat is said to be found; at Otterswick, in Sanda, I have seen the people digging it at low water for fuel. The peat was mainly composed of twigs and leaves, and the seeds of the birch were plentifully scattered through it. There were also many gnarled pieces of wood, of the thickness of a man's arm. I was informed, on describing the kind of peat found at Otterswick, that the same sort of fuel may be got at Balranald, on the west of North Uist, at the level of low water. Peat also occurs below mud and gravel between tidemarks at the head of West Loch, Tarbert, in Harris; and Martin, the historian of the Hebrides, speaking of Pabbay, an island in the Sound of Harris, says, "The west end of this island, which looks to St Kilda, is called the Wooden Harbour, because the sands, at low water, discover several trees that have formerly grown there. Sir Norman Macleod told me that he had seen a tree cut there, which was afterwards made into a harrow." Several traditions could be added, of places now submerged that were formerly the sites of chapels or houses; and I think it may be taken as proved, that since the commencement of the peat-forming era, the land has sunk or subsided twelve.

feet at least; how much more, there are no means of finding out, for the submarine peat may have grown near to, or far away from, the high-water level; neither do we know how far the submerged peat-banks extend beyond the level of low water. From the foregoing facts, it may be inferred that very soon after the climate of the Hebrides became such as to admit of the growth of vegetation, man emigrated to these shores, bringing with him the arts of agriculture and navigation, and a religion that induced him to honour the memory of his illustrious dead. Since then the tanned vegetable mould has accumulated to the height of at least five feet, and also since man's advent here the entire land has sunk twelve feet or These data may, by a more extended investigation, form a measure to the time of his arrival; at present I must content myself with having pointed out the facts.

more.

IV. Description of several Fishes from Old Calabar. By JOHN CLELAND, M.D., Glasgow. Communicated by WILLIAM TURNER, M.B.

The specimens now exhibited were given me by our late lamented Treasurer, Mr Oliphant, and it was his desire that they should be shown to this Society. They come from Old Calabar. They are not in very good preservation, but are sufficiently so for the determination of their characters. Besides a small specimen of Chromis niloticus (Cuv.), there is an Eleotris and four fishes of the family Siluroidei, none of which correspond with species described in the work of Cuvier and Valenciennes, or such other books as I have been able to consult. They may possibly be mentioned in recent monographs which I have not had an opportunity of seeing.

1. The Eleotris presents well the characters of that genus, the head being much depressed, the body slender, the eyes remote, the gape very large for the size of the body, and the lower jaw prolonged beyond the upper, so as to give the mouth an upward direction, which may probably be looked on as convenient to a fish inhabiting the muddy parts of the water, and preying upon animals swimming overhead. Also, it shows well the appendage behind the vent and the ununited ventral fins, which distinguish this genus from Gobius. It has no vomerine teeth; its scales are small; its total length to the tip of the caudal fin is five inches. The caudal fin is one inch long and rounded.

The number of the fin rays is as follows:-first dorsal eight, second dorsal ten, caudal thirty-two, anal nine, pectoral sixteen, ventral six.

2. Of the Siluroid specimens one is a Synodontis, and corresponds exactly with a specimen in the British Museum. I believe that it is the Synodontis serratus, although the number of its fin rays agrees rather with that attributed to S. arabi in the work of Cuvier and Valenciennes. The anterior dorsal fin has eight rays, the first of which is, as in all the members of the genus, a long and strong slightly curved spine fixed at right angles to the body. This spine is toothed on its posterior edge, and towards the point anteriorly.

The posterior or fatty dorsal fin, half an inch high and two inches long, 3 A

VOL. II.

is continued further back than the posterior margin of the anal fin. _The caudal fin is bifurcated, the superior half longer than the inferior. From the longest ray above to the longest below, inclusive, there are seventeen rays; and outside these there are eleven shorter rays in each half. There are thirteen rays in the anal, nine in the pectoral, and seven in the ventral fin. The first pectoral fin ray in Synodontis is a large spine toothed before and behind, the posterior teeth being longest, about equal in length to the dorsal spine. There is no locking arrangement in its joint, and therefore it can only be kept in the extended position by muscular effort. On the other hand we find the lock-joint of the pectoral spine in genera in which the dorsal spine is not fixed, as in this genus.

The superior scute of the head passes back nearly as far as the third dorsal fin ray. The coracoid scute is triangular, and passes back as far as the superior scute.

The long curved teeth which hang loosely in the lower lip, and which give character to the genus, are twenty-four in number. Behind them are fine velvety teeth, the patches of opposite sides distinct. In the upper jaw there is a double row of conical teeth, about eighteen on each side, and behind them (on each side) a patch of setose teeth of very irregular size.

There is one superior pair of barbules very long and simple, and two inferior pairs, both of them branched, the outer pair half the length of the superior pair, and the inner pair half the length of the outer.

The specimen is twelve inches long from mouth to tip of tail, and three inches from mouth to the first dorsal spine.

A view of the swimming-bladder of Synodontis is given by Müller in his work on Myxinoid fishes.

3. Two of the specimens exhibited belong to the genus Clarias, which is characterised by the presence of arborescent branchial appendages attached to the second and fourth branchial arches, and by having only one dorsal fin.

The first of them corresponds exactly to one which I have had the opportunity of examining in the British Museum, and which, therefore, we may expect to have properly described by Dr Gunther in his elaborate work, of which part is already published. The specimen is a foot long. The head is depressed and shielded, oblong in form, the eyes small and lateral; the body is oblong, compressed. The dorsal fin extends from within an inch behind the head back to the tail, but is not continuous with the caudal fin; it contains seventy-six rays, the first of which is not spinous.

The caudal fin contains twenty-four rays, the anal sixty-three, the pectoral twelve, the ventral six. The first ray of the pectoral fin is a spine toothed before and behind, and having a lock-joint, that is to say, its joint is so constructed that when the spine is fully extended it cannot be pushed back towards the body by any direct pressure, but must first be rotated to a certain extent, and then it folds back easily. The anal fin is continued, like the dorsal, back to the caudal, without being continuous with the latter. There is a papilla behind the anus.

The teeth are velvety, in very broad patches. The teeth in the upper jaw are larger than those in the lower; the patch in the lower jaw is broader than that in the upper, and indented at the outer side. On the vomer there is also a broad patch of very minute teeth.

The barbules are eight in number. The anterior superior pair are longest, the external inferior pair slightly longer than the posterior superior pair, while the internal inferior pair are thick, short, and truncated, a character peculiar to this species.

4. The other Clarias, which I exhibit, resembles two of the Indian

species, viz., Clarias Nieuhoffi and Clarias jagur, in the dorsal and anal fins being continuous with the caudal. It has only one arborescent branchial appendage on each side, which is attached to the fourth branchial arch, and is very small. The specimen is eight inches long to the tip of the caudal fin, the latter being three-fourths of an inch long. The head is depressed, not shielded, three-fourths of an inch long, the body compressed. The barbules are eight, the branchiostegal rays nine. The anterior superior barbules are broadly membranous at the base

The teeth are velvety, the patch on the lower jaw is much larger than that on the upper, and there is a patch on the vomer.

The dorsal fin begins an inch behind the head; it has no spinous first ray. The rays in it and the anal fin are very numerous. The pectoral fins are small, and have six rays, the anterior ray being a short spine, less than half the length of the succeeding rays, and not lock-jointed. The ventral fins are small and contain three rays.

5. The remaining specimen is a species of Heterobranchus. Heterobranchus is a genus allied to Clarias, having the same sort of arborescent branchial appendages, but having two dorsal fins, the posterior of which is fatty.

The specimen is five and a half inches long, three-fourths of an inch of this length belonging to the caudal fin. The appendages will be seen on the second and fourth branchial arches.

The head is very much depressed, broad, shielded, the eyes lateral, the barbules eight.

The branchiostegal rays are eight. The first dorsal fin has thirty-five rays, the first one not spinous, it ends behind the middle of the body. The fatty dorsal fin extends from the true dorsal to the tail, and contains traces of eighteen very fine rays. The caudal fin has twenty-two rays; it is rounded, and is tipped with black, as are also to a less extent the other fins, and the dorsal aspect of the head is also black. The anal fin has forty-seven rays, and extends from anus to tail. The pectoral fin has ten rays, the anterior ray toothed and lock-jointed, shorter than the succeeding rays. The ventral fin has six rays.

The teeth are velvety, in elongated narrow patches, one of which is on the vomer.

V. Note of the Common Squirrel (Sciurus vulgaris) Feeding on Birds and their Eggs. By THOMAS DURHAM WEIR of Boghead, Esq., Bathgate. Communicated by Dr JOHN ALEX. SMITH,

The far-famed Charles Waterton of Walton Hall, Esq., near Wakefield, in his amusing and highly interesting Essays on Natural History, has strongly maintained that the squirrel derives its supplies of food wholly from the vegetable kingdom, and is not possessed of any carnivorous propensities. I shall however prove from a few facts, for

"Facts are chiels that winna ding,

And canna be disputed,"

that this is not the case, but that some members of this family are not true vegetarians, and do occasionally indulge in carnal feasts.