Four years ago M. R. D. M. Verbeek, Director of the Geological Survey of the West Coast, Sumatra, placed in the hands of my friend Prof. T. Rupert Jones, F.R.S., for description, a collection of fossil remains obtained by him in the prosecution of his geological researches in Central Sumatra, accompanied by some notes and sections of the geology of this little-known region of the globe.

On this part of the Yorkshire coast, the storms of last winter have often bared parts of the beach, for a time, of their usual covering of sand and shingle, and have thus exposed to observation many interesting features in connexion with the Drift series. Of these, the most instructive point which has come under my notice is the one which forms the immediate subject of the present communication.

Since the publication, in the Quarterly Journal of Science for July, 1876, of an article on the Indian Diamond Fields, in which the writer, Captain Burton, does not appear to be aware of what has been done in these Colonies towards adding to our knowledge of the geological history of the diamond, I have been induced to re-write a paper, jointly prepared by the late Professor Alex. M. Thomson, of the Sydney University, and myself, and read before the Royal Society of New South Wales on the 7th December, 1870; and to incorporate with it a series of my own papers (of which the above was merely a summary), which appeared in the “Sydney Morning Herald” previously to that date. I shall confine my remarks to the mode of occurrence of the diamond in New South Wales, as the late Rev. W. B. Clarke has, in his valuable and interesting Presidential Addresses to the Royal Society of New South Wales in 1870 and 1872, almost exhaustively treated the subject, as far as regards our present knowledge of the diamond all over the world.

Kames, åsar, and minor topographical features.—Kames and åsar are usually found associated. Indeed, the one class of elevations shades into the other so gradually that it is sometimes impossible to draw the line between them. Though the kames may occur singly, they are often in ranges of several, perhaps extending for miles. Each is usually elliptical in outline, and its longer axis corresponds in direction with the range. The åsar are frequently intercepted by channels of erosion, by which they are divided into ranges of oblong hills, the direction of which is very nearly the same as that of the kames proper. In Dubuque county, Iowa, where these features have been most thoroughly studied, this direction is about S. 75° E. Within 40 miles south-west from there the direction changes to abut S. 45° E., and in the next 50 miles the direction becomes a trifle west of south; and this is the general direction over the greater part of the region examined.