The Rev. A. Irving, in the January Number of the Geological Magazine, p. 46, writes: “The argument then in favour of the retention of the name ‘Permian’ (as against e.g. that of ‘Dyas’) is based on no logical consistency with established geological nomenclature. It is an excellent local name for the Russian series, but as a general term for the European series it is highly misleading.”

The Sauropoda are now generally recognized by anatomists as a well-marked order of the Sub-class Dinosauria. In the previous articles of this series, the main characters of the two families of this order (Atlantosauridæ and Morosauridæ) already named by the writer have been given.3 A third family is represented by the genus Diplodocus, a study of which, more especially of the skull, throws light on the whole group of Dinosaurian reptiles.

Shell conical, moderately long, with perhaps a rudimentary umbilicus. The complete spire would consist of about 10 whorls, which increase under a regular angle. The surface of the apical whorls in this specimen is not well preserved, but the five anterior whorls are in good condition; they are smooth, somewhat tumid towards the centre, and separated by a suture of moderate depth. Wavy longitudinal lines, apparently lines of growth, are observed, but there is no trace of any other ornament. Base of body-whorl smooth and almost polished, except where there has been a decortication of the outer layer of shell. This decortication, besides affecting a considerable area near the outer lip, has formed a belt in the posterior region of the base, thus producing a sort of false carination. In this way we learn that both inner and outer layers of shell were of considerable thickness. (N.B.—The shell is now mainly in the condition of spathic iron, coated and coloured with brown oxide).

There can be no doubt that the name Megalichthys was originally suggested to Agassiz by the gigantic teeth of the great round-scaled fish first brought into notice by the researches of Dr. Hibbert, in the quarries of Burdiehouse, though indeed some of its remains had long previously been figured by Ure in his “History of Rutherglen and East Kilbride.” Incontrovertible evidence of this may be found by referring to the Proceedings of the British Association for 1834, and to Dr. Hibbert's original memoir on the Burdiehouse Limestone published in the Transactions of the Royal Society of Edinburgh, vol. xiii. 1835. But with the remains of this enormous creature were also associated and confounded certain rhombic glistening scales, belonging really to a considerably smaller fish of a totally different genus, and when Agassiz, subsequently to the meeting of the British Association at Edinburgh in the year above quoted, found in the Museum at Leeds a head of this latter form, or at least of an allied species, he adopted it, by description and by figure, as the type of his Megalichthys Hibberti, relegating the other to the genus Holoptychius. This latter, the real “big fish,” is now known as Rhizodus Hibberti, the founder of the genus being Prof. Owen; and though it may be a matter of regret that it did not retain the name Megalichthys, the laws of zoological nomenclature do not admit of any alteration now.

The Oyster-bed (Ostrea Bellovacina) in the lowest part of the “Woolwich-and-Reading” series is well known as constituting an interesting horizon in the Lower Eocene formation; but, as it is not throughout persistent in the range of this group of strata, every instance of its occurrence is worth recording. It is well known in Berkshire at Clay Hill, Shaw, about a mile N.E. of Newbury; and it occurs further westward near Hungerford (Prestwich, Quart. Journ. Geol. Soc. vol. x. pp. 85 and 87). We now know of its occurrence to the South of Newbury, from the works of the new railway intended to connect Newbury and Southampton.

In the interesting description of a faulted slate (Geol. Mag. Jan. 1884, p. 1) by Mr. J. J. Harris Teall, the writer appears to consider that all faults are due to up-and-down movements; while he seems to ignore the horizontal or transverse heaves, that is, movement of the strata from side to side. In the newer strata, which are not much moved from their original horizontal position, such as those of the South Staffordshire Coalfield, or of the Weald, the majority of the dislocations appear to be due to upward or downward movement; but this is not the case among the older contorted and crumpled rocks, where in general the horizontal heaves usually equal, if they do not exceed, the up-and-down faults in number. Consequently, while reverse faults are rare in nearly horizontal rocks, they are not uncommon among the contorted and crumpled strata.

In my former Paper (see Geological Magazine, 1884, Decade III. Vol. I. pp. 73–78) I endeavoured to show that as the elevation of mountain-ranges caused cold, so their subsidence in long periods of time was the cause of a warm temperature.

[The following list of localities in New Zealand where the remains of the Dinornis have been discovered has been most obligingly drawn up for me by Mr. Charles Smith, an old resident in New Zealand, and I gladly publish it as a useful list for reference. —Edit. G. M.]