I found at Clune no ichthyolite to which the geologists have not been already introduced, or with which I had not been acquainted previously in the Cromarty beds. The Lower Old Red of Morayshire furnishes, however, at least one genus not yet figured nor described, and of which, so far as I am aware, only a single specimen has yet been found. It seems to have been a small delicately-formed fish; its head covered with plates; its body with round scales of a size intermediate between those of the Osteolepis and Cheiracanthus; its anterior dorsal fin placed, as in the Dipterus, Diplopterus, and Glyptolepis, directly opposite to its ventral fins; the enamelled surfaces of the minute scales were fretted with microscopic undulating ridges, that radiated from the centre to the circumference; similar furrows traversed the occipital plates; and the fins, unfurnished with spines, were formed, as in the Dipterus and Diplopterus, of thick-set, enamelled rays. The posterior fins and tail of the creature were not preserved. I may mention, for the satisfaction of the geologist, that I saw this unique fossil in the possession of the late Lady Cumming of Altyre, a few weeks previous to the lamented death of her ladyship; and that, on assuring her it was as new in relation to the Cromarty and Caithness fish-beds as to those of Moray, she intimated an intention of forthwith sending a drawing of it to Agassiz; but her untimely decease in all probability interfered with the design, and I have not since heard of this new genus of ichthyolite, or of her ladyship's interesting specimen, hitherto apparently its only representative and memorial. In the Morayshire, as in the Cromarty beds, the limestone nodules take very generally the form of the fish which they inclose: they are stone coffins, carefully moulded to express the outline of the corpses within. Is the fish entire?--the nodule is of a spindle form, broader at the head and narrower at the tail. Is it slightly curved, in the attitude of violent death?--the nodule has also its slight curve. Is it bent round, so that the extremities of the creature meet?--the nodule, in conformity with the outline, is circular. Is it disjointed and broken?--the nodule is correspondingly irregular. In nine cases out of ten, the inclosing coffin, like that of an old mummy, conforms to the outline of the organism which it incloses. It is further worthy of remark, too, that a large fish forms generally a large nodule, and a small fish a small one. Here, for instance, is a nodule fifteen inches in length, here a nodule of only three inches, and here a nodule of intermediate size, that measures eight inches. We find that the large nodule contains a Cheirolepis thirteen inches in length, the small one a Diplacanthus of but two and a half inches in length, and the intermediate one a Cheiracanthus of seven inches. The size of the fish evidently regulated that of the nodule. The coffin is generally as