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150 they ought to have been. It is not to be disputed that at the junction with granite and basalt, compact limestone and chalk are often converted into marble, as in Paradies-backen, near Drammen, in Norway, and near Belfast, in Ireland; but, in the case of granite, the dry method of conversion cannot be any longer tenable, since the experiments of Sorby, Delesse, and others, have altered our conviction of its origin. Such changes, then, cannot be regarded as due to heat alone, and that they were assisted by other agencies is a conclusion arrived at also by Bischof in a different manner.

In the Anniversary Address to the Geological Society, the President, Mr. Leonard Horner, commented on these experiments in the following manner:—"With every respect for my friend the Professor, I think that I may turn round upon him and say that he has been somewhat hasty in considering that his experiments prove that mistakes were made by Hall in his descriptions of the results of his numerous experiments, all agreeing while obtained in so many different ways; for the Professor states that in both of his experiments the gun-barrel burst (at what stage of the experiment, he does not say) and thus one of the essential conditions in Hall's experiments was wanting, viz. continued great pressure. I consider therefore that these experiments of Professor Rose in no degree invalidate those of Hall, so long considered to support, in no inconsiderable degree, the hypothesis of Hutton."

.—Some remains of Enaliosauria, recently found in the shales at the top of the Rhætic series, zone of Ammonites planorbis (Wright), exposed near Droitwich, are of more than ordinary interest. One, unfortunately much distorted, skeleton of Ichthyosaurus intermedius still holds, in the space between the ribs, the contents of the stomach, which, however, do not present any different features from the example described and figured by Dr. Buckland, being chiefly scales of pholidophorus leptocephalus and some indeterminable fragments of Echinidæ, probably of Cidaris Edwardsii, the spines of which occur very abundantly in these shales. Jaws of Ichthyosaurus tenuirostris have also been met with in fine condition in this little-known locality. The specimens have been carefully collected, and are now in the cabinet of Richard Smith, Esq., of Westacre, near Droitwich.

Fish-remains in these Lower Liassic beds should be more attentively searched for. I have just received a letter from a noted microscopist, relating to the otolithic bone of Pholidophorus, which makes a fine object in the microscope.—.

.—At the Zoological Society, on the 28th Januaiy, Professor Owen read a paper on the anatomy of the Aye-Aye (Cheiromys Madagascariensis). The only point of interest to geological and paleontological readers was the part of the paper in which Professor Owen entered into the evidence afforded by the peculiarities of this animal on the question of the origin of species; after showing the arguments in favour of the derivative hypothesis, and those against its mode of operation as propounded by Buffon, Lamarck, and Darwin, became to the conclusion that, whilst the general evidence on this subject was in favour of creation by law, he was compelled to acknowledge ignorance as to the mode in which such secondary causes might have operated in the origin of Cheiromys. At the same time Professor Owen fully admitted that the attempts to dissipate the mystery which environed the origin of species, whether successful or not, could not but be fraught with great collateral advantages to zoological science.