We are told that Lord Chatham once excused himself for not paying due attention to the speech of a political rival by saying, that he felt that man was responsible to the Creator that his time should not be wasted by hearing discourses which neither conveyed profit or amusement to the hearer, nor honour and dignity to the speaker. We were reminded forcibly of this anecdote by reading in our esteemed contemporary the ‘Parthenon,’ a few weeks ago, a paper entitled “Likes and Similitudes,”—a title very like that of an Adelphi farce.

It has been observed by metaphysical writers, that every object in the world must be either like or unlike some other object, and consequently, there can be no difficulty in instituting either a comparison or a contrast between any two things. For those readers then, who, like the zoologists ridiculed by Forbes, have a vivid perception of analogy, but not of affinity, as well as for that far more numerous class who can but perceive differences, without being able to decide whether they are dependent upon analogy or affinity, the perusal of “Likes and Similitudes” will afford insipid and innutritive mental repast, akin in nature to that which regales poetic minds entranced over the pages of the ‘Sentiment of Flowers’ or ‘The Language of Plants.’

I gave, in a paper in the February number of the ‘Geologist,’ a general view of the facts in the geology of this country which have led me to believe that the metamorphosis of rocks is due to a slow and gradual change in their constituents ; of which change water is one of the chief agents, and the internal heat of the earth not a necessary adjunct.

I now propose to describe more particularly those relations of the quartzite with the palæozoic rocks, a careful examination of which has rendered necessary an entire reconstruction of the geological map of the country. That map, published in the Transactions of the Geological Society, was the work of an able man, and the evidence on which the Devonian (Upper Silurian, Bain) was separated from the Clay-slate formation was (so far as I have been able to verify it), I believe, such, that he would not have been justified in coming to another conclusion by any generally admitted principle of the science; for this reason, I invite the criticism of European geologists on my facts and inferences, and their aid in solving many difficulties which still remain unexplained.

I stated in my former Paper that the plains and lower hills and valleys of the coast region, extending from Cape Town to the mouth of the Fish River, were formed of blue slaty and sandy rocks. These were all referred to one formation by Lichtenstein.

The fossil represented in the accompanying figures is one of that kind whose discovery severely tests the faith of the naturalist in his previous conclusions, and may appear to raise a suspicion not only respecting the sufficiency of his data, but even as to the correctness of his method of investigation. Almost any person, at first sight of the specimen, would think he was looking at a coral, and it would seem like an attempt to impose on one's credulity to say it was a bivalve shell, like an oyster or a clam.

Yet there is no doubt it is a kind of Hippurite, although the rays give it a novel and extraordinary character. The discoverer had quite satisfied himself on this point before he brought it to England and placed it in our hands. It was found last year (January, 1861), by Mr. Lucas Barrett, F.G.S., Director of the Geological Survey of the British West Indies, in the parish of Portland, in the north-east of Jamaica. This part of the island, lying to the north of the principal range of the Blue Mountains, which run east and west, is itself mountainous, rising to the height of 7000 feet. The hippurite limestone is well seen on the banks of the Back river, a tributary of the Rio Grande, at about fifteen miles from the coast.

The lower mandible of a chimæra—the first discovered in the Lower Greensand—is now in the collection of Sir Philip Egerton, who informs me it belongs to the species Ischyodus Agassizii. Since this discovery I have met with many more specimens, some of smaller size; but, from the difficulty of extracting them from the stone, I have never succeeded in getting one so perfect. Several good specimens have been procured from the Lower Chalk at Burham. The chimæra approaches in form to the shark tribe, but it is far from being so ravenous in its disposition. Recent species are found in the Arctic and in some of the European seas, and attaining the length of two or three feet. Being often taken in the company of the herrings in their migrations, it has thus gained the patronymic of “king of the herrings.” The mouth of this odd-looking fish is furnished with hard and undivided plates instead of teeth, four of which are placed on the upper and two on the lower jaw.

Fossils are very rare in the succeeding “rugged flint layers,” which have an average thickness of eight inches.