In this paper I purpose giving a history and description of the Cretaceous group of Aporrhaïs, as far as they are at present known to me, especially of those forms which are so beautifully preserved in the Gault of Folkestone, and so-called Upper Greensand of Blackdown. I regret that I cannot include the Aptien and Neocomien species, but the collections at present open to me are too meagre to give anything like a complete account of them. In the whole group there are even now many points which require further research; the correlation of some of the forms with those on the Continent is still unsatisfactory, from the difficulty experienced in comparing actual specimens. The figures available, even in the most modern works, appear in some cases to have been restored, and not therefore to represent the form of any shell that has been really met with.

3. Third Period of Volcanic Activity in the Lipari Islands.

Although, as we have already seen, the older volcanic formations of the Liparis present us with features of no little interest, yet it is on account of the cones and lava-streams, composed of rocks of singular beauty and almost unique character,—which are the product of the latest developments of igneous action in these islands, that the attention of geologists is most frequently directed to them.

A meteoric iron, weighing 407 tolas (about 10 lbs.), fell at Nidigullam, and penetrated the ground to the depth of twenty inches. Those who saw the meteor describe it as very large and beautiful, and as exhibiting increased brilliance when it burst. The explosion was followed by a series of rumbling noises. The meteorite passed over Parvatypore from N. to S.; the people of the village were greatly alarmed, and one man, near whom it fell, was stunned. The villagers “carried it off to their temple, and, much alarmed, were found making púja to it.” The author of the notice in the Proceedings considers that this aerolite contains no stony matter, and he states that it is marked with striæ lying obliquely to its greatest length, which is 6½ inches. The lamented Dr. Stoliczka, however, was of opinion, from the description of the striation, that it is a stone containing much iron, “like the Mooltan aerolite which fell some short time ago.”

It is not a little remarkable that, while almost every part of England and Scotland, and particularly the district of “the Lakes” and North Wales, has been abundantly studied and written about,—and while Ireland also has been almost completely surveyed,—the Isle of Man should not only have been left untouched by the Geological Survey, but, latterly at least, should have well-nigh escaped the attention of geologists altogether. With the exception of three or four papers by the Rev. J. G. Cumming, published in the Quarterly Journal of the Geological Society, and their embodiment in a more popular form in his History of the Isle of Man, and Guide Book, scarcely anything appears to have been written upon the geology of the island, besides some Memoirs published in the infancy of the science, or a few brief notices of special points since.

As I have paid some attention to the Eskers of Ireland, perhaps I may be allowed to make a few notes on the papers of Mr. F. J. Jamieson recently read before the Geological Society of London, and the letter of M. Jespersen that appeared in the Geol. Mag. for December, 1874. These observers put forward the theory (if I understand them rightly) that these peouliar ridges of shingle, gravel, and sand may be in part glacial, they having been accumulated as marginal fringes to the different stages of the ice-cap that at one time covered the northern portion of the Continent of Europe, as it intermittingly retreated. This suggestion seems worthy of consideration, as possibly, if the ice-cap had an intermittent retrogression, there would be fringes or ridges of shingle, gravel, and sand marking each rest, formed of the detritus from each successive portion of the ice that disappeared; but such accumulations should be at different altitudes, and being carried by water off the ice, and deposited successively at its edge, should be stratified outwards,—or if the margin was retreating, they would be jumbled together.