A stalactitic curtain on the right-hand side presents a very singular appearance, its surface being covered with an abundant crop of tiny club-like bodies about one-tenth of an inch in length, and consisting each of a shining drop of water, enclosing a minute fungus. These may possibly explain in some degree the peculiar fungoid-appearance of certain small bosses of dripstone which I have met with in the caves of Pembrokeshire: for an accumulation of carbonate of lime on such a nucleus would produce the forms which they assume (see Fig. 17). There are also magnificent groups of dripstone, and each joint in the rock is adorned with lines, and pipes, and fringes of calc spar, or widened out into roof-shaped hollows, and traversed by deep, vertical grooves, caused by the passage of water laden with carbonic acid. The general surface of the roof, where the rock is bare, has had its fossils etched out by the acidulated water. In one place you may stand under a branching coral, with its sides and base distinctly marked, and in another fossil shells stand out almost in their original beauty. _Rate of the Accumulation of Stalagmite._ The rate at which the calcareous matter is being deposited at the present time is very easy to be estimated, for that accumulated since the passage was cleared out is white, and contrasts with the dirty, grey-red colour of the older kind. In one case a thickness of 0·24 had been formed in thirty-five years, by the water flowing down the side of the passage excavated by Mr. Farrer, while in another, in about the same time, 0·05 inch had been formed. This would give an annual accumulation of 0·0068 in the one case, and in the other about one-fifth of that amount. This rate does not agree with the rate of increase noted by Mr. Farrer and Professor Phillips in the case of a large stalagmite called the Jockey Cap, on which a line of drops is continually falling from one point in the roof. Its circumference in 1839 measured 118 inches, in 1845, 120 inches, and in 1873, I found it to be 128 inches. The annual rate of increase from 1845 to 1873 is ·2941 inch, and that from 1839 to 1845 is ·2857. I found, however, that the most remarkable increase was that in height. In 1845 its apex was 95·25 inches from the roof, in 1873, 87 inches, which would imply an annual deposit of not less than ·2946. (See Appendix II.) At this rate it will arrive at the roof in about 295 years. But even this comparatively short lapse of time will probably be diminished by the growth of a pendant stalactite above, that is now being formed in place of that which measured 10 inches in 1845, and has since been accidentally destroyed.