I have been favoured by P. N. H. Jones, Esq., engineer of the Waterworks, with specimens from a boring at Sangregrande undertaken by the Government of Trinidad with a view to ascertain the extent and position of the Tertiary coal-seams of that district and other facts. The specimens consist of a dark-coloured (blackish) sand-rock, finely (but slightly irregularly) laminated, the lamination being at an angle of about 50° from the horizontal. The samples came from 150, 250, 400, 500, and 600 feet deep below the surface. I examined each one separately, but as the differences between them, whether as regards mineral constitution or organic contents, are only slight, and in fact two portions from the same depth show often as much difference as samples from different depths, I shall describe the whole together. These specimens are from boring No. 3, Plate VII.

The Arenig Series, as originally defined by Sedgwick, has undergone much subsequent modification by its founder and other authors. There have been separated off from it the Tremadoc Series at the base, and the Llandeilo Series above, and a certain amount of ambiguity has arisen as to what constitutes the Arenig thus restricted; possibly, therefore, the recognition of three well-defined graptolite sub-faunas within the series in certain districts may help in some degree towards the solution of the problem.

Among the collections now in Cairo I find several new mammals, the remains of which have been collected by Mr. Beadnell, for the most part during the last few months. Brief descriptions of these new forms are now given in order that the names may be included in the lists in Mr. Beadnell's forthcoming report on the geology of the Fayûm area.

Pterodon macrognathus, sp. nov.

This creodont is known from the nearly complete left ramus of the mandible. The last molar, the first premolar, and the incisors are represented by the alveoli only, but the other teeth, with the exception of the canine, the crown of which is broken off, are in fairly good condition. The mandible is long and narrow from above downwards, the distance between the last tooth and the condyle being remarkably great. The transversely elongated cylindrical condyle is about on a level with the alveolar border, and is separated from the prominent angle by a deep notch; the coronoid region is imperfect.