At least seven geological ages ago, and there were aeronauts in those days. Not Glaishers and Coxwells, clinging to bubbles of gas at six miles high, but reptiles and birds,—the latter at least, and perhaps the former, capable of long and lofty flights. On the red sands of Connecticut, perhaps some two or three ages before, wingless birds had left their footprints; but nor bone nor feather has the searching eye of man yet looked upon to glean a notion of what those birds were like. Not from all the thick mass of stratified rocks deposited by lake or ocean in the long interval between the period of those impressed tracks—persistent through 2000 feet of stone—to the time when a solitary bone was entombed in the sandy mud of the Cretaceous Sea.

A little time ago the geological and palæontological worlds were astonished by the announcement of a feathered reptile. We recorded the reports without comment; the reason was, we could not rightly reconcile the statements to our conscientious content. We endeavoured to procure drawings, but without success; the specimen was for sale, and no doubt its value would have been prejudiced by its portraits being handed about as “cartes de visite” in the houses of the learned. The accounts that reached us were second-hand and by hearsay. Professor Wagner, on his death-bed, wrote the notice in the ‘Sitzungberichte’ of Munich, from the description of a M. Witte, who had derived his information from a sight of the specimen in M. Häberlein's possession.

Since the original foundation of the genus Dichobune by Cuvier, and the critical observations made thereon by Owen, the national collection has continued to receive new accessions, indicating the existence of a certain range of variation in the molars of that genus.

The specimen (No. 30673) in the British Museum collection, is figured in Plate II., by Mr. Mackie. It consists of the three molars of the right side of a species of small quadruped closely resembling Dichobune. The length of the fractured ramus containing these teeth, of which the inner aspect is exposed to the observer, measures 27mm.; its greatest vertical depth between the penultimate and last molar being 11mm.

The last molar (m 3) measures 7mm. in length, and 4 in breadth. Its form is quadricuspid; the two outward cusps being least eroded; from the ectoposterior cusp is developed a slight basal talon, extending towards the entoposterior cusp, which is the smallest of the four, pyramidal, and acuminate; the entoanterior cusp is larger, and is tipped with a small exposed ring of enamel; the ectoanterior cusp is much worn; there is no trace of the distinct hinder lobe of Xiphodon, which lobe in the Dichobune (sp. ?) from Hordwell, marked 29714 in the British Museum, exhibits a well-marked bicuspid division, having the effect of rendering the ultimate molar in that specimen virtually hexacuspid, to a greater extent than in the Dichobune ovina.

Though our science has risen above the stage from which she taught that all granites are parts of the original crust of the earth; though she has advanced so far as to doubt whether, in all cases, the granitic was the first phase of rock-existence which the materials composing it assumed, and to entertain the question whether such rocks may not be the extreme form of metamorphism, which has obliterated all traces of an earlier condition; and though she may prudently decline to point out, in the large circle of her rocky acquaintances, one mass of crystalline unstratified rock which, as such, can be proved to be older than some known beds of mechanical origin; it remains to be the rule rather than the exception to meet with persons, frequently veil-informed, and not without an interest in geology, who still cling to the notion, or allow it to cling to them, that every mass of granite is a primitive rock, in the strict chronological import of the term; and represents a period in the earth's history prior to the possible existence of sedimentary strata, or of organized beings. Indeed the opinion that granite is, in all cases, a primary rock, has so large a place in the public mind, that one might prudently hesitate before throwing such a question as “What is the age of the Dartmoor granite?” before any audience having a very large admixture of the popular element.

The existence of layers of limestone at various intervals among the rocks, while in the intermediate strata there is a remarkable deficiency of that substance, is a fact which I have not seen hitherto satisfactorily accounted for, but of which we may hope to find some rational explanation.