The Geological Department of the British Museum is much indebted to Dr. Cowper Reed for his careful description of the Girvan fossils which he assigns to Cornulites (Geol. Mag., Vol. LX, 1923, pp. 268–76). A slight correction, unfortunately, is necessary. Various specimens received from Mrs. Robert Gray as “Tentaculites” were registered in the Department under the numbers correctly quoted by Dr. Reed. He himself, in returning the specimens to us, pointed out, also correctly, that some of them were of quite different nature. He omitted, however, in some instances, to remove those numbers from the lists that he quoted. To prevent further confusion, the numbers to be cancelled are given below. At the same time, opportunity is taken to quote the number of the specimen that is hereby selected as the holotype of each new species. The numbers then remaining will denote the paratypes.

As an illustration of the difficulties encountered in basing the classification on some peculiarity of the Ammonoid suture-line the case of the two families Macroscaphitinæ and Crioceratinæ may again be referred to, the former of lytoceratid, the latter of hoplitid origin. Distinction between these two families was based on the bifid or trifid characters of the first lateral lobe. Hamulina nitida, v. Koenen, which shows very nearly equal-sized suture elements, has the trifid first lateral lobe of the type-species of Hamulina, namely S. dissimilis, d'Orbigny, but the plain shell of the lytoceratid Anahamulina. Hyatt put the latter into his family Macroscaphitidæ, but the former, and also the clearly lytoceratid Pictetia, into Ancyloceratidæ, i.e. even into a different sub-order. But Anahamulina subcylindrica, d'Orbigny, sp., i.e. the type-species itself, has a nearly trifid first lateral lobe, though it is connected through A. Lorioli, Uhlig, sp. (with a sub-bifid first lateral lobe), with typically lytoceratid forms. In ornament and coiling also Hamulina resembles certain lytoceratid forms (compare e.g. the various forms of Macroscaphitinæ figured by Uhlig).

In the course of collecting in the Ballycastle coalfield, the species described in this note were obtained. Details of the associated fauna will be found in the forthcoming memoir of the Geological Survey of Ireland relating to the district. It is only necessary to, mention here that the beds from which the present material comes are, in the memoir, referred to a D2 horizon.

When writing a general account of the Upper Chalk of England for vol. iii of the Cretaceous Rocks of Britain (Mem. Geol. Survey, 1904), I stated the belief of Mr. W. Hill and myself that the British Tipper Chalk comprised more than one division of the value of a stage. We grouped the zones then recognized into two divisions, pointing out that the lower zones were essentially the Chalk with Micrasters and the upper zones the Chalk with Belemnites; but we did not systematically adopt these divisions as stages with definite names.

Spheroidal concretions from the Yarra estuary which were to found to contain plant-remains were described by Mr. Chapman recently in this journal. The structures in themselves are of considerable interest to geologists, and also to palæobotanists from the fact that they contain “matted fragments of woody and foliaceous-material.” They were made the subject of some comparisons with the calcareous concretions from the Lancashire Coal-measures, and as a result certain general considerations were brought forward, which call for comment, and which are of sufficient importance to receive attention.

Natural compact ice is not wholly crystalline. Salt solution is present in glacier ice at temperatures down to −21·72°, and is probably located at the intergranular boundaries. The proportion of brine is normally very small, but becomes considerable near 0°.

The special mechanical properties at the intergranular contacts, the “Hugi effect” on melting, the phenomena of regelation, and the infra-red absorption, indicate that the molecules at these contacts are in the amorphous state. This may be the case in ice free from salts.

Internal flow takes place by relative displacement of crystalline portions by means of slip:—

1. along the basal planes of the crystals,

2. along intergranular surfaces,

3. along fracture surfaces within the individual crystals.

Processes 2 and 3 are facilitated by the presence of liquid at the surfaces of slip, and it is the regelation power of this liquid which preserves the cohesion of the deformed masses.

The liquefaction at points of compression, transference of the liquid, and its congelation elsewhere, is an important factor in the formation of compact ice from névé, but is of secondary importance in the flow of compact ice.

The processes by which ice suffers deformation are those which operate in the flow of all crystalline masses, the comparative ease with which it is deformed being an instance of the weakness of rocks near their melting temperatures. Ice at hundreds of degrees below its melting point would compare in strength and hardness with the other crystalline rocks which exist under like temperature conditions in the outer part of the earth's crust.

Among the many singular discoveries made in the ruins of Pompeii, and deposited in that most interesting of Museums, the Museo Borbonico, in the city of Naples, are a variety of shells, principally species now found in the Mediterranean Sea, and so far of interest as an illustration of the persistency of certain known species within the historic period, no difference whatever being observable between the disinterred and living specimens. On a close examination I observed, besides those from the neighbouring seas, species from distant countries, for example:—Conus textilis, Triton femorale, Meleagrina margaritifera (Pearl Oyster), species only found in the Indian and Eastern seas. I think, therefore, that this may be regarded as part of a Natural History collection. Assuming the truth of this conjecture, its antiquity is without a precedent. Did the original proprietor form one of a Natural History Society of Pompeii, of which the distinguished Naturalist Pliny, who perished at Pompeii, was a member? It would also be curious, in these days of research for priority of names, to know how they were described. Such a discovery might disturb existing nomenclature, and increase the perplexity already felt in naming collections. But laying aside fanciful conjectures, the collection is further instructive from the condition and perfect preservation in which the specimens are found, after an interment of nearly 1,800 years. Besides the collection in the Museo Borbonico, there is still standing in a villa at Pompeii, a fountain decorated with shells of the Mediterranean, one species of which, viz. Murex Brandaris, retains its colour and general freshness and is not to be distinguished from living examples; while the same species, from the Italian Tertiaries, are colourless and in that friable condition characteristic of shells even of the most recent geological period, pointing, like other discoveries, to the great antiquity of the most modern Tertiary deposits as compared with the era of the human race.

There is no positive evidence that any species of Nerita has been found in the Corallian Rocks of Yorkshire. It is true that Nerita lœvigata, Sow., is quoted by Phillips (G. Y. 1875, p. 258), but this fossil is well known to be a Monodonta, and it is doubtful if the exact form occurs on this horizon (see postea, Turbo Erinus). The same author also quotes “Nerita bullata” as occurring in the Coralline Oolite. I can find no reference to this species, and am at a loss to understand what fossil is intended to be thus designated. There are casts in the Coral Rag of North Grimston which may belong to a species of Nerita.

At the last meeting of the Society, Mr. Plant made statements respecting the supply of so-called fossil shells from the Drift at Macclesfield, of a striking and curious character: he warned geologists against certain specimens, on the grounds that some were only recent shells sold as fossils, and others, though bearing the appearance of Drift-fossils, were not only spurious as such form Macclesfield, but were not even fossils at all, being nothing but the results of an elaborate system of importation and manufacture: forgeries, in fact, to meet a new demand. Mr. Plant allowed that some of these frauds were well calculated to deceive even geologists, and quoted a statement that they had been successful at the Museums of London, Liverpool, and Manchester. Besides the simple introduction of recent shells, he specially reported a process of fecthing such shells from recent beaches at Liverpool, Southport, or Ireland (even the use of West Indian African shells), the breaking-up of the same, and the subjection of the fragments to fire or acid, and a subsequent treatment by friction in a basket with gravel, ‘to give them the true Drift-character and the necessary redtinge.’

The object of this paper is to show that the received explanations of the structure of mountain chains will not account for the formation of certain Precambrian ranges, and to state facts in support of a new theory of the origin of some mountains. A brief summary of the ordinary views of the subject will first be necessary.

In this country the best known species of Tetradella is T. complicata (Salter), a form which is usually regarded as typical of Caradoc rocks and has been widely quoted in faunal lists as such. It happens, however, that this species was originally described as Beyrichia complicata, by Salter (Phillips and Salter, 1848, p. 352, pi. 8, fig. 16) from the Llandeilo Beds of Llan Mill, near Narberth, and it is extremely unlikely that it ever occurs in Caradoc beds. This confusion has no doubt arisen from the inaccuracies in Salter's original figure, the briefness of the accompanying description and the fact that McCoy figured what is obviously another species of Tetradella under the same name from the Caradoc Beds of Pont y Meibion (McCoy, 1851, pl. IE, fig. 3). At a later date T. R. Jones refigured T. complicata from Llan Mill with more accuracy than Salter and with a fuller description, but unfortunately figured under the same name a form from the Caradoc of Harnage, giving also a list of Llandeilo and Bala localities where T. complicata was supposed to occur (Jones, T. R., 1855, pp. 163–5, pl. vi, figs. 1–5). In addition to this figures have appeared in various textbooks and similar works of a general nature which are usually too poor for specific determination although it is obvious that in the main they cannot be referred to Tetradella complicata (Salter).

The first American mammal found in the Jurassic, and a large proportion of those since discovered, belong to a peculiar family which the writer has called the Dryolestidœ. It includes several genera and numerous species from America, and is likewise represented among the forms found in Europe.

A number of coarse-grained blocks, consisting of forsteritic olivine, chrome-diopside, calcic plagioclase, and chromite in varying proportions, were found in an ankaramitic basalt on Faial. With one exception, the blocks show remarkably little alteration. There is no evidence of zoning in any of the minerals. Indications of strain are frequent. Dark scoriaceous material is often present along intercrystal boundaries and fractures. The textures and gradations in composition suggest that these blocks were formed by crystal accumulation.

A new Ordovician stromatoporoid species, Labechia aldonensis, is described and illustrated from the Stinchar Limestone (Barr Group) of the Girvan District, Scotland.

The cardinal process in the Productidae is divided into two main types, either bi- or trilobed. The process in several species, illustrating each type, is described and figured, and the development of both types compared.

During the last two and a half years I have been engaged in the study of the Cornish Veinstones in the field and in the laboratory by microscopic and other methods, and have come to the following conclusions:—

This Plesiosaur was collected from the Oxford Clay at Peterborough by A. N. Leeds, Esq., F.G.S., and was acquired for the Hunterian Museum, Glasgow University, by Professor J. W. Gregory. The specimen has many striking resemblances to Cryptocleidus oxoniensis, but detailed examination showed that it could not belong to that species, and the differences existing in the paddle, shoulder-girdle, number of vertebræ, and conditions of ossification are such that it cannot be retained in that genus as now defined. The paddle closely resembles that of Tricleidus, but the shoulder-girdle alone is sufficient to prevent the inclusion of the specimen in that genus. It seems advisable to create a new genus, and as it may be some time beforea full description can be published a preliminary account is here given.