in Scotland — Eggs of Batrachians (?) in a lower division of the "Old Red," or Devonian — Footprints of Lower Carboniferous reptiles in the United States — Fossil rain-marks of the Carboniferous period in Nova Scotia — Triassic Mammifer from the Keuper of Stuttgart — Cretaceous Gasteropoda — Dicotyledonous leaves in Lower Cretaceous strata — Bearing of the recent discoveries above-mentioned on the theory of the progressive development of animal life.

Tracks of a Lower Silurian reptile in Canada.—In the year 1847, Mr. Robert Abraham announced in the Montreal Gazette, of which he was editor, that the track of a freshwater tortoise had been observed on the surface of a stratum of sandstone in a quarry opened on the banks of the St. Lawrence at Beauharnais in Upper Canada. The inhabitants of the parish being perfectly familiar with the track of the amphibious mud-turtles or terrapins of their country, assured Mr. Abraham that the fossil impressions closely resembled those left by the recent species on sand or mud. Having satisfied himself of the truth of their report, he was struck with the novelty and geological interest of the phenomenon. Imagining the rock to be the lowest member of the old red sandstone, he was aware that no traces had as yet been found of a reptile in strata of such high antiquity.

He was soon informed by Mr. Logan, at that time engaged in the geological survey of Canada, that the white sandstone above Montreal was really much older than the "Old Red," or Devonian. It had in fact been ascertained many years before, by the State surveyors of New York (who called it the "Potsdam Sandstone"), to lie at the base of the whole Silurian series. As such it had been pointed out to me in 1841, in the valley of the Mohawk, by Mr. James Hall[vii-A], and its position was correctly described by Mr. Emmons, on the borders of Lake Champlain, where I examined it in 1842. It has there the character of a shallow-water deposit, ripple-marked throughout a considerable thickness, and full of a species of Lingula. The flat valves of this shell, of a dark colour, are so numerous, and so arranged in horizontal layers, as to play the part of mica, causing the rock to divide into laminæ, as in some micaceous sandstones.

When I mentioned this rock in my Travels[vii-B] as occurring between Kingston and Montreal, (the same in which the Chelonian foot-prints have since been found,) I spoke of it as the lowest member of the Lower Silurian series; but no traces of any organic being of a higher grade than the Lingula had then been seen in it, and I called attention to the singular fact, that the oldest fossil form then known in the world, was a marine shell strictly referable to a genus now existing.

Early in the year 1851, Mr. Logan laid before the Geological Society of London a slab of this sandstone from Beauharnais, containing no less than twenty-eight foot-prints of the fore and hind feet of a quadruped, and six casts in plaster of Paris, exhibiting a continuation of the same trail. Each cast contained from twenty-six to twenty-eight impressions with a median channel equidistant from the two parallel rows of foot-prints, the one made by the feet of the right side, the other by those of the left. In these specimens a greater number of successive foot-marks belonging to one and the same series were displayed than had ever before been observed in any rock ancient or modern. Mr. Abraham has inferred that the breadth of the quadruped was from five to seven inches. A detailed account of the trail was published by Professor Owen, in April 1851, from which the following extracts are made.

"The foot-prints are in pairs, and the pairs extend in two parallel series, with a channel exactly midway between the right and left series. The pairs of the same side succeed each other at intervals, varying from one inch and a half to two inches and a half, the common distance being about two inches. The interval between the right and left pairs, measured from the inner border of the small prints, is three inches and a half, and from the outer border of the exterior or large prints, is seven inches. The shallow median track is one inch and a quarter in breadth, varying in depth, but not in its relative position to the right and left foot prints."

"The inference to be deduced from these characters is, that the impressions were made by a quadruped with the hind feet larger and somewhat wider apart than the fore feet, with both hind and fore feet either very short, or prevented by some other part of the animal's structure from making long steps; and with the limbs of the right side wide apart from those of the left; consequently, that the quadruped had a broad trunk in proportion to its length, supported on limbs either short, or capable only of short steps, and with rounded and stumpy feet, not provided with long claws. There are faint traces of a fine reticulate pattern of the cuticle of the sole at the bottom of some of the foot-prints on one portion of the sandstone; and the surface of the sand is generally smoother there than where not impressed, which, with the rising of the sand at the border of the prints, indicates the weight of the impressing body. The median groove may be interpreted as due either to the abdomen or the tail of the animal; but as there is no indication of any bending or movement of a tail from side to side, it was probably scooped out of the soft sand by a hard breast-plate or plastron. If this were so, it may be inferred that the species was a freshwater or estuary tortoise rather than a land tortoise."[viii-A]

Previously to this discovery, the trias was the oldest stratum in which any remains or signs of a Chelonian had been detected. Numerous other trails have since been observed (1850-51) in various localities in Canada, all in the same very ancient fossiliferous rock; and Mr. Logan, who has visited the spots, will shortly publish a description of the phenomena.

Chelonian foot-prints in Old Red Sandstone, Morayshire.—Captain Lambart Brickenden has just communicated to the Geological Society of London a drawing and description of a continuous series of no less than thirty-four foot-prints of a quadruped observed in the course of last year (1850), on a slab of sandstone quarried at Cummingstone, near Elgin, in Morayshire, a rock which has always been considered as an upper member of the Devonian or "Old Red."[ix-A] A part of the track, the course of which was from A to B, is represented in the annexed woodcut, fig. 521. The foot-prints are in pairs, forming two parallel rows, which are somewhat less distant from each other than those of the Lower Silurian tortoise of Canada above mentioned. The stride, on the other hand, is four inches, or twice that of the Beauharnais Chelonian. The hind foot is exactly of the same size, being one inch in diameter, and larger than the fore foot in the proportion of four to three.