In the November Number of this Magazine (Vol. X. p. 481) the Rev. O. Fisher has called attention to the formation of the Fleet, Dorsetshire, and puts forward suggestions as to its formation in opposition to the sub-aerial denudation theory of Messrs. Bristow and Whitaker. To me the formations of the Fleet and Chesil Beach seem easily explained, as similar beaches are not uncommon on other parts of the English coast, and also on that of Ireland; but inland behind many of these banks the spaces that were formerly lagoons are now reclaimed land.

In 1830 Pander proposed the genus Porambonites for a remarkable group of Lower Silurian Brachiopoda, which abound in the neighbourhood of St. Petersburg, in Esthonia, and other parts of Russia; as well as in rocks of a similar geological age in Great Britain, Portugal, and other countries.

Spec char.—Corallum ramose, the branches cylindrical, of a diameter of from a line and a half to two lines, dividing dichotomously at intervals of about half an inch, but not anastomosing. Corallites oblique to the surface, with exceedingly thick walls. Calices extremely minute, about one-eighth of a line in their longest diameter, sub-circular, transversely oval, or sub-triangular, level with the surface, and having the lower lip hardly or not at all prominent. Intervals between the calices proportionately very wide—usually about half a line.

As a further contribution to the subject of mountain elevation, of which the Editor of the Magazine has given an interesting and lucid résumé in his late Presidential Address to the Geologists' Association, I send an outline of a paper which was read by me in December before the Cambridge Philosophical Society.

The cause of the formation of mountains is so difficult and so vast a question that I cannot undertake to answer all Captain Hutton's objections to what he concisely calls the “contraction” theory. Moreover, I feel that, as far as my endeavours can help to elucidate so great a subject, I shall do better to throw what I have further to say into a form which is not controversial. I desire not to be held a champion of any theory, and shall always honestly abandon any position, which subsequent consideration leads me to think untenable. Thus with respect to paragraph (7), p. 26, in Captain Hutton's rejoinder to my critique, I refer to the abstract I have sent to the Magazine of my paper lately read at Cambridge, for it supersedes some of the purely tentative suppositions to which Captain Hutton takes exception, and which I adopted six years ago as “not unreasonable,” in order to test the application of the theory.

Mr George Maw, in the Geological Magazine, Vol. IV. pp. 24 and 299, has described a number of sections in Flintshire and Denbighshire in which white clay or sand occurs under Boulder-clay. A newly-exposed section near Colomendey Hall, about three miles from Mold, is very important on account of the complete series of glacial drifts by which the white clay is overlain. I lately examined it in company with Mr. Manning, of the Chester Natural Science Society.