In the Geological Magazine for July appears an article by Mr. Charles Dawson on Ancient and Modern Dene Holes. As Mr. Dawson mentions Essex deneholes, and comes to conclusions contrary to those arrived at by Mr. Cole and myself, the authors of the Report of the Essex Field Club on the Deneholes of Hangman's Wood, near Grays Thurrock, I shall be glad to be allowed space for a reply. For though our views do not appear to be injuriously affected by Mr. Dawson's remarks, yet as the Denehole Report is now more than ten years old it is probable that few of the readers of the Geological Magazine have both seen and remember it. And the impression which the reader would derive from Mr. Dawson's article is, that his Bell Pit hypothesis is something quite new, and therefore unnoticed by us, whereas it was an old view before the Report was written, having been put forward by the late Roach Smith in the Gentleman's Magazine in 1867; and an account of workings for chalk, of the kind described by Mr. Dawson, written by Mr. F. J. Bennett, of the Geological Survey, is appended to the Denehole Eeport.

Rock-Basins have been getting out of favour of late. The “heckling” which they have suffered from my friend Mr. Marr tempts one to echo Betsy Prig's classic remark about Mrs. Harris. Mr. Brend, however, though “dealing faithfully” with them in the September number of the Geological Magazine, does permit one or two to exist on sufferance, so that I feel minded, were it only as an act of charity to these depreciated securities, to describe two or three examples in the Alps which I think must be true rock-basins.

On April 30th, 1897, the Trustees of the British Museum purchased from Dr. F. Krantz, of Bonn, seven specimens labelled “Agelacrinus, n.sp., Unter Devon, Condroz, Frankreich.” But the Condroz is a district in Belgium, south of Namur and yiege, between the rivers Meuse and Ourthe; the species do not belong to Agelacrinus or any known genus; and the matrix clearly is that of the well-known “Psammites du Condroz,” which are Upper, not Lower, Devonian. The species, however, is new, and would have been described by me many months ago had it not been necessary to compare it with other species as rare as they were obscure.

All students of Carboniferous geology will hail with pleasure Mr. W. Gunn's masterly paper in the August number of the GEOLOGICAL MAGAZINE (p. 342), and it is only to be regretted that the publication of such important stratigraphical facts should have been delayed for so long; but however useful from the numerous facts it contains, I must take exception to the deductions made from them. The paper is a remarkable one, because, while having for its object the correlation of rocks which occur over a wide expanse of country, no appeal has been made to palseontological evidence to clinch the author's views which are based on purely stratigraphical considerations.

Proceeding in a westerly direction from Tammerfors, we stopped near the station of Siuro to examine some railway cuttings where good sections of gneissose rock and mica-schist, both of Pre-Bothnian age, occur. Macroscopically, the gneissose rock is distinctly and regularly foliated, having small, lenticular, streaks of quartz abundantly disseminated. Locally, however, the section in the field exhibits much contortion; and thin, irregular, veins of quartz, manifestly of secondary origin, are not uncommon.

This is undoubtedly the most difficult district to deal with, and one in which I have had to change my views on certain details. Still, there is one part of it where the evidence is very clear, namely, the ground between the railway and the road at the Tan-y-pant inlet.

Having, in March last, received from Mr. Jukes-Browne, F.G.S., of the Geological Survey, a small carapace of a crab obtained by Mr. J. Scanes, of The School House, Maiden Bradley, from a quarry in the Chert Beds of Baycliffe, near Maiden Bradley, Wilts, I endeavoured to identify it with some species of Cretaceous Necrocarcinus already described, but without success. I am therefore reluctantly compelled to refer it to a new species. The specimen is rather imperfect, which renders the task of determining its characters the more unsatisfactory.

A Collection of Invertebrate fossils, obtained from various horizons and localities in Egypt and consisting principally of molluscan remains, has been sent home for examination and description by Captain H. G. Lyons, R.E., Director of the Geological Survey of that country.

The oldest specimens represented belong to Upper Cretaceous rocks, and are dealt with in the present communication. They include one species of Gasteropod and eight Lamellibranchs, two of the latter group being regarded as hitherto undescribed forms. It need hardly be stated here that most of our knowledge respecting these groups of Mollusca as represented in Egypt during this period has been ably summarized by Professor Dr. von Zittel, in his elaborate memoir, “Beiträge zur Geologie und Palaeontologie der Libyschen Wiiste und der angrenzenden Gebiete von Aegypten,” published in the Paleaontographica for 1883. For subsequent details we are mainly indebted to the researches of Professor Mayer-Eymar and Prof. Johannes Walther: to the former for his monograph, “Zur Geologie Egyptens,” which includes a list of Cretaceous shells from the neighbourhood of the Great Pyramid; and to the latter for his paper, “L'Apparition de la Craie aux Environs des Pyramides,” containing a list of molluscan species from the same distinct and horizon, though particularly localized as Abu Eoasch, Golea, etc.

A paucity of Gasteropod species is noticeable in the faunistic lists of the Upper Cretaceous period of Egypt, with, however, a large representation of bivalve mollusca. The most abundant forms appear to belong to the genus Ostrea and its allies, a fact also observable in the corresponding faunas of Algeria and Tunis. In all three countries a similar conchological facies is apparent, whilst some species show a marked resemblance to Syrian forms. Certain difficulties have arisen in assigning a satisfactory horizon to the Egyptian species here discussed, though the evidence appears to be in favour of a Turonian age—an opinion somewhat suggested by the palaaontological work of M. Jules Welsch, who has discovered in Algeria, Sphærulites (Sauvagesia) Sharpei, Bayle, a typical Turoniiin shell of Portugal, associated with Ostrea acanihonota, O. Boncheroni, etc. This author, therefore, inclines to the belief that the majority of Algerian species hitherto recognised by Coquand, Peron, and others as of Santonian age, are more probably Turonian. If this be accepted, then the Cretaceous rocks near Cairo (Abu Roasch, etc.), containing similar shells, which have been considered as Senonian by Schweinfurth, Walther, etc., should equally be regarded as Turonian, though apparently the Portuguese mollusc, Sauvagesia Sharpei, has not yet been identified in Egypt.

The section in which these rocks are exposed is seen in a field at a distance of about a quarter of a mile from the village of Martley and due north of Berrow Hill Farm. Here is a small excavation for road stone, but it does not appear to have been worked lately. Both the quartzite and syenitic rock are exposed, the latter being very decomposed. The relations of the rocks to one another appear to be as follows (see Figure):—Below, at A, the quartzite is seen to stand out conspicuously. Round this, as at B, is a thin layer of powdery rotten rock, differing but little from the rest of the decomposed syenite, forming a crust at C, but evidently marking the junction of the quartzite and syenite; the latter being at D and E sufficiently undecomposed to allow of its being sliced. Above comes a loose breccia consisting of fragments of these rocks, but this is evidently surface soil.

The object of this paper is an attempt to furnish proof of what JL has been a growing conviction in the mind of the writer, that the true age of the Dartmoor granite, and probably its associated line of bosses running south-westwards into Cornwall, might be referable to an interval or period of geological time between the Lower and the Upper Culm, or Carboniferous system.

In the present state of Natural Science, there are too many obstacles in the path of the original investigator. That this is the case in the study of Botany, we may well believe, as authorities of that science have frequently placed the fact on record. It is certainly true that everyone who does original work in systematic Zoology, either among the living or extinct forms, meets many difficulties at the start in endeavouring to ascertain what others have done before him. The literature of the subject is often discouraging from its extent, and especially from its uncertainty. If the work in hand requires the comparison of type-specimens, the difficulties greatly increase, and often prevent definite conclusions. The type will frequently be found the most important element in the problem, far more so than the literature, however extensive. This is more especially true among the extinct vertebrates, with which the present communication mainly deals.

In September last the Committee appointed by the British Association to “examine the conditions under which remains of the Irish Elk were found in the Isle of Man” commenced excavating at Close-y-garey, near Poortown ; but owing to the unusual amount of water, considerable labour and expense were incurred in the preliminary work of draining, and by the 25th September the grant was exhausted.

In rearranging the Carboniferous fossils in the Woodwardian Museum, I met with a specimen labelled Aihyris, n.sp., which reminded me of the form described by De Koninck as Terebratula serpentina. On careful examination I am convinced that it belongs to this species, and the following is a description of our specimen:— Shell subovate, terebratuliform, widest at about one-third its length from its anterior edge. Valves moderately convex, slightly flattened anteriorly, and devoid of sinus and fold; margin entire and regular. Ventral valve a little less deep than dorsal valve, and furnished with a slightly recurved beak truncated by a large circular foramen, bordered in front by a pair of deltidial plates. Surface of both valves ornamented with straight, radiating, very faint ribs, 60 to 70 in number, arranged in a regular close series separated by weak narrow furrows. Some of the ribs bifurcate at about half their length, and those near the hinge-line curve gently backwards. Shell substance finely punctate. Concentric strife of growth are distinct on both valves. Length, 25 mm.; breadth, 22 mm.; dorsiventral diameter, 12 mm.

[For a period of nearly sixty years Sir Joseph Prestwich recorded his geological observations in a series of notebooks. These records, together with the illustrative sections, were afterwards copied, in many instances, into folio volumes dealing respectively with the Eocene and Miocene, the Pliocene and Post-Pliocene formations, and with well-sinkings, springs, etc. The systematic arrangement and indexing of his very copious notes no doubt greatly facilitated the labours of the author. The majority of his notes and sections have been published, but here and there among the notebooks and MSS. there are records of pits and railway-cuttings, as well as some statements of opinion, which appear never to have been printed. A selection of these is now given, together with references to published papers dealing with the same subjects. All additions are put in square brackets.

It was the desire of Sir J. Prestwich to have dealt more fully with the phenomena of the Glacial Period, but owing to the many calls upon his time, and to his aim invariably to obtain and to submit fully to his readers all the evidence bearing upon his subjects, he was led to postpone for many years his more elaborate works. Thus his important papers on the Crag formations were issued long after most of his observations had been made. Meanwhile other geologists had entered the field and made known many of the facts which he had previously gathered, a proceeding natural enough and one by no means to be regretted. Thus Sir J. Prestwich remarks in his paper on the Westleton Beds, Part I (Quart. Journ. Geol. Soc., vol. xlvi, 1890, p. 86), that “The Memoirs of the [Geological] Survey, to which I shall have frequent occasion to refer, now supply a mass of valuable details, which greatly facilitate the task and do away with the necessity of much local description.” The notebooks rarely contain any particular expressions of opinion; they simply record facts and only occasionally suggest correlations. The conclusions were for the most part worked out subsequently and embodied in various published papers.

Among the MSS. left by Prestwich is the rough draft of the Table of Contents of a paper dated 1892. It includes the following heads:—]

Moreseat is in the parish of Cruden, in the east of Aberdeenshire. It lies at an elevation of 300 feet above sea-level, and the surface of the ground slopes to the sea at Cruden Bay, distant five miles to the south. On the north the ground rises gradually, reaching the height of 450 feet above sea in Torhendry Ridge, which is strewn with chalk-flintsingreat abundance.