Principal Dawson, of Montreal,. Canada, has placed in my hands for description a remarkably interesting specimen, indicating a species of the genus Cephalaspis in transatlantic Silurio-Devonian beds. He writes, “The specimen was found by one of my assistants, Mr. G. F. Kennedy, B.A., when collecting with me, in a bed charged with remains of Psilophyton, on the north side of Gaspé Bay. The geological horizon is below the middle of the Gaspé Sandstones, but several hundreds of feet above their actual base, so that the specimen may be regarded as either Lower Devonian or Lower Middle Devonian.

No very perfect example of this species appears to have been collected; the one figured in my plate was kindly given to me by Sig. Meneghini. The shell is ovate and smooth, about ten lines in length by nine in breadth; the valves are moderately convex, and there exists a deepish sinus in the ventral valve to which corresponds an elevation or fold in the opposite one. Ter. Voglianei occurs in a yellowish marl in the Lower Miocene at Dego, and along with it is found a small Terebratulina, which may probably be a variety of T. caput-serpentis.

The transition or passage-beds between any two large formations are always difficult to make out, and those between the Old Red Sandstone and the Silurian are no exception to the rule. Much light has recently been thrown upon the latter, yet much more is needed before the exact order and position of their different beds can be considered as finally decided.

The forms which Mr. Davidson in his invaluable Monograph has included under T. ovoides, are so various that it would be possible to refer the shells figured in the plate to that species, but since T. trilineata, from the Inferior Oolite, and T. lata and T. ovoides, from drift-blocks—which I shall endeavour to show are of the very latest Jurassic horizon—are very different in many respects, I prefer to give a new name to this form, which may find its place near T. ovoides and T. simplex. The specimen drawn, Fig. 1 and la, is from the collection of Mr. Roper of Lowestoft, who obtained it, with another specimen, from a gravel-pit at Thorpe in Suffolk. It has the general simple form of T. ovoides, but is remarkable for its great size. The imperforate valve is flattened in the mesial line, whilst the perforate valve is deep and raised into a well-pronounced keel in the mesial line extending from the beak; the foramen is small. The specimen figured is longer than the other in Mr. Roper's collection, which has the shorter, squarer form of Fig. 2, resembling T. simplex. This fine Terebratula may be known as T. rex.

Inasmuch as the subject of the Fossil, or rather Sub-Fossil Mammalia of Ireland, has been brought rather prominently before the notice of the Society during the past two sessions, I have considered that it might not be devoid of interest to our members, if I were to place on record the various genera and species of that class of which remains have been hitherto found in Ireland. Such a communication as this does not make any claim to originality, and I shall endeavour, as far as I can, to give my authority for every statement of a fact which will be embodied in this Catalogue. The chief sources from which the information has been derived are Dr. Scouler's papers, in our “Journal,” and those by Dr. Ball and Sir W. Wilde, in the “Proceedings of the Royal Irish Academy.”