Professor Charles Lap Worth, in his “Sketch of the Geology of the Birmingham District”, gives a list of species (pp. 343 and 349) from “the Hyolite Limestone” and the associated shales as provisionally determined by Miss E. M. R. Wood (Mrs. Shakespeare). He referred the beds generally to the Lower Cambrian and paralleled them approximately with the fossiliferous beds of Comley, the details of which had not then been worked out. The present study of the Hyolithidæ, etc., of Woodlands Quarry, fully confirms the reference to the Lower Cambrian, and it would seem that the position of the Hyolite Limestone in the faunal sequence is near to or a little below that of the Olenellus and Grey Limestones of Comley at the local summit of the Lower Cambrian. The evidence of this is indirect, for no species has yet been identified from both localities, unless it be Micromitra labradorica, Billings sp. Nevertheless, the Hyolithidæ, etc., found in North America that are nearest to, or representative of, those of Hartshill, are there associated more or less intimately with a number of trilobites and brachiopods that find their representatives in the Comley Limestones.

From time to time I have been given an opportunity to discuss in the Geological Magazine the question of the cause or causes of climatic variations. The subject is one of deep interest to the geologist. Even Lyell, in the first edition of his Principles of Geology, gave a good deal of space to it, but contented himself with merely pointing out that variations in the distribution of the land would lead to changes in the climate. He wisely limited himself to this aspect of the question, for, at that time, the directions of the winds in middle latitudes were not such as meteorological theory would have led us to expect.

During the last year I have examined, through the kindness of Mr. E. O. Forster Brown, Min. Eng., borings that have been put down by Messrs. Bell Bros., at Cotefield Close and Sheraton, near the southern limits of the Northumberland and Durham Coalfield. They are situated about 5 miles west of Hartlepool, and about 8½ miles east of the Permian escarpment at Ferryhill. The boring at Cotefield Close lies about 1½ miles east of Hurworth Burn station, and about the same distance south of that at Sheraton. The details of the former are from my own notes which were taken when the hole was finished, but those of the Sheraton cores are by Dr. C. T. Trechmann, who examined them as they were brought up from time to time, it thus being possible to obtain a very full record. I also desire to thank this geologist for some notes on the Sheraton boring which are incorporated in this paper. Both of the boreholes passed through the superficial deposits and Permian strata into the Coal-measures, but as that at Sheraton has just entered the lastnamed series and is not yet completed, the remarks on the Carboniferous rocks refer only to the strata pierced at Cotefield Close. The examination of these cores adds to our knowledge of the Permian, confirming some of the points that Dr. Trechmann and I have enunciated in previous papers dealing with the Magnesian Limestone.

The variability and occasional instability of the Ammonoid suture-line, to which attention has been drawn, the recurrence of similar types, and the frequent asymmetry of the opposing halves of a given suture-line, which is apparent not only in the Dactylioceras commune, figured by Swinnerton & Trueman (fig. 9 on p. 42), but also in the development of the suture-line in e.g. Pseudosageceras multilobatum, Noetling, in Indoceras baluchistanense, Noetling, or in Oxynoticeras oxynotum, Quenstedt, sp., to mention only a few well-illustrated examples, might be thought to impair the usefulness of the suture-line for the classification of Ammonoids. Yet, long before there was any subdivision of “Ammonites” at all, the greatest importance had been attached to the foldings of the suture-line, and Pictet stated in 1854 that “the lobes in their essential traits furnished very constant and very valuable characters”. Von Buch's group of “Arietes” was well characterized by the general plan of the suture-line, namely, the deep siphonal lobe and the short external saddle, only most authors would put more reliance on the ornamentation of the shell and put such a form as Asteroceras sagittarium, Blake, sp., into the genus “Aegoceras.” The writer would even go so far as to say that the type of suture-line given by Mr. Buckman for “Defossiceras” defossum, Simpson, sp., should not be found at the horizon stated, and that the form probably will turn out to be an Arietid (Agassiceras) of semicostatum age.

“Structure of the Anorthosite Body in the Adirondacks,” by H. P. Cushing. Journ. Geol., vol. xxv, pp. 501–8, 1917.

A criticism of Dr. Bowen's conclusions as to the field relations of the different rock-types of the area.