Avicularia of what I have called the Lesueuri-type are not confined to Membranipora. There are at least two species provided with them which come nearer to Semieschara.

The discussion on the origin of the Himalayas, started by Sir T. H. Holland's review of Colonel Burrard's memoir, appears to have been led, by the concluding sentence of that review, into an unprofitable channel; for alike in the review and in the succeeding articles by Mr. Fisher and Colonel Burrard it seems to have been accepted that only two theories are applicable, firstly, Mr. Fisher's discussion of the theory of the disturbed tract contained in chapter x of the first and chapter xiii of the second edition of his Physics of the Earth's Crust, and, secondly, that developed by Colonel Burrard. Further, it is assumed that the former is dependent on the hypothesis of a fluid earth and the latter such as should follow from the hypothesis of a solid, highly heated, and cooling globe: the connexion, in either case, being so close that the acceptance of one or other hypothesis, of the constitution of the earth, necessitates the acceptance of one and the rejection of the other of the theories of the origin of the Himalayas.

I am content to leave to the readers of the Geological Magazine the question whether Colonel Burrard's theory of the elevation of mountains and Mr. Hayford's of the distribution of density to cause isostasy are more in accordance with geological phenomena than my theory of mountain roots supported in a dense liquid substratum. But in Colonel Burrard's reply to my paper in the Magazine for June there is a fundamental but specious error. I wrote: “Is it not possible that the earth's rotation may impart to it a ‘gyroscopic’ quasi rigidity, which may enable it to withstand the deforming influence of external forces [the attraction of the moon and sun], although at the same time forces internal to the earth will be unaffected by it.” To this Colonel Burrard replies: ”Mr. Fisher has argued that the rotation of the earth will give to the liquid interior an effective rigidity; but this rotation has conferred no rigidity upon our oceans, and even if it did render the liquid interior rigid, it would only do so in low latitudes where the rotation velocity is high. I understand, moreover, that the earth's interior was assumed by Mr. Fisher to be liquid, in order to explain the floatation of the crust. If the liquid is now proved to be rigid, the crust cannot be floating upon it.”

The great Karroo System of South Africa was divided by its discoverer, Andrew Geddes Bain, into four formations on lithological characters. They are—

The Stormberg Series.

The Beaufort Beds.

The Ecca Beds.

The Dwyka Series.

It has long been recognized that the Dwyka conglomerate, which forms a large part of the lowest series, is of glacial origin, and the common occurrence of smoothed and striated pavements below it all along its northern exposure seems to show that it is the product of a great continental ice-sheet.

Dr. Nathorst mentioned to me in 1910 the fact that the rhizomes of Equisetum columnaris had not been observed, and I offered to show him a place where I thought they would be found. He had not time to visit the section on that occasion, but in the following year Dr. T. G. Halle accompanied me to the exposure and agreeably to expectation the rhizomes were found within a few minutes of our arrival.

In the April number of this Magazine a review appeared of Colonel Burrard's memoir on the origin of the Himalaya Mountains. The writer, Sir T. H. Holland, in it refers to a paper of mine originally published in the Phil. Mag., and subsequently in an amended form as Appendix No. 1, 1905, Indian Survey Papers, professional vol. xviii. I shall be glad to make a few remarks upon the subject. After duly crediting me with having partially anticipated the results now obtained by the Survey, by calculating the deflection of the plumb-line in North India which would follow from my theory of mountain compensation by a ‘root’ extending to a depth of about 29 miles, the reviewer continues— “The variations now observed are, however, more violent than those expected by Mr. Fisher, for the northerly deflections of the plumb-line decrease to zero at a distance of about 15 instead of over 60 miles from the visible foot of the hills.” I would reply that I have not calculated the deflection at 15 miles, and it is not safe to guess a priori what it would be. The numerical calculation for a given distance is tedious, and I could not now undertake it.

The species Eugeniacrinites stramlergensis was described by me in 1912 (pp. 161, 167, pi. iii, fig. 2) on the evidence of a single specimen (A). Examination of a better specimen (B), subsequently acquired, and believed to be of the same species, has convinced me that, though the species appears to belong to the family Eugeniacrinidæ, Zittel, still it belongs to none of the known genera. This new genus, it is true, resembles Apsidocrinus in the union of its interradial processes, which, form a kind of vault above the patinal cavity (Jaekel, 1907, p. 304; Remeš, 1912, pp. 163, 168), but it differs from that genus in the form of the interradial processes, and especially in the size and shape of the radial facets.

More than fifty years since a great impulse was given to the study of a new and strange group of Palæozoic Arthropoda whose remains were almost simultaneously brought to light in New York, in England, Scotland, and in the Baltic island of Oesel, and attracted the attention of numerous palæontologists both in this country and in America. Among others may be cited Hugh Miller and the elder Agassiz, who at first believed them to be fish (1844), but the latter afterwards was convinced that they were in reality the remains of an enormous Crustacean.

It is now time to turn to the consideration of the part played by these organisms in the formation of sedimentary rocks through the successive geological periods.

Some time after the year 1850 d'orbigny recognized, among a collection of fossils from Cuba, a species that he referred to the genus Galerites under the name of G. lanieri. The description and figures of the species were to have been included in vol. viii of the Historia física, político, y natural de la isla de Cuba, but the part of that work that should have contained them seems not to have been published.

The following account of the genus Syringothyris is the result of work undertaken at the suggestion of Professor T. F. Sibly, and is intended as a preliminary to a revision of the British species of that genus, which I hope to present at some future date.

In 1908 Mr. R. H. Worth described a number of stones which had been dredged by Mr. T. R. Crawshay, of the Marine Biological Association, from the floor of the English Channel to the east and south-east of the Lizard. These stones included a great variety of rocks such as granites, felsites, diorites, and other igneous rocks, gneisses, schists, slates, and quartzites, Devonian grits, Permian conglomerate, Triassic marl, sandstones of different kinds, Liassic limestones, hard chalks, and flints.

At various places, such as the north side of Garabal Hill, the two Garabal burns (loc. iv and v, Fig. 1), and elsewhere, remarkably coarse rocks are found. A good section showing an apparent passage from tonalite to a coarse hornblendite is exposed at loc. v (Fig. 1). The rock in the bed of the burn is the normal tonalite, which appears to pass gradually to diorite. A closer examination of the unweathered rocks, however, shows that the passage is only apparent, and that the tonalite is clearly intrusive into the diorite with sharp junctions. The diorite near the junction is a rock of porphyritic aspect, containing large crystals of zoned diopside, abundant green hornblende and felspar, while the amount of quartz is small. A good deal of biotite is present, so that the rock might be described as a pyroxenemica-diorite. Within a few feet the rock becomes coarser in texture, and the felspathic content diminishes, while there is a corresponding increase in the amount of amphibole. The latter is the green hornblende common to the diorites, and is occasionally replaced by mosaics of secondary actinolite.

The original figure of this species was rather diagrammatic and requires supplementing. Figs. 1 and 2 are from the type-specimen, Fig. 2 being given to illustrate the rectangular aperture which the species has a tendency to develop, though quite irregularly; this rectangular outline appears to be due to the amalgamation of the two prominent tubercles into a straight-edged cap which hides the arched part of the upper lip and may be oœcial in function. The typical form of the species is definitely established in the Marsupites zone (= Marsupites band of many authors), though it only becomes abundant in the succeeding zone.

While mapping the Upper Devonian and Carboniferous Rocks in North Devon I took the opportunity of examining the raised beach of Barnstaple Bay and the deposits resting upon it. As a result of my observations I found that the sequence of these deposits is identical bed for bed with that of Cornwall, South Wales, and Southern Ireland, except that in place of the Boulder-clay there is in North Devon a bed of clay with striated stones which may not be of glacial origin. The position of the Boulder-clay over the ancient head, however, corresponds with the position of the bed of glaciated stones and indicates the infra-Glacial age of the ‘head’. The fact that the ‘head’ is contemporaneous with ‘Coombe Rock’ has been held by all geologists familiar with the subject. It is a fact of first-class importance with regard to the relationship of man to the Glacial period, for it proves that man existed before these Boulder-clays were deposited. The evidence is inferential and supplied by the occurrence of Palæolithic implements of Le Moustier type in the Coombe Rock of Southern England and France. Granting, then, that the Le Moustier period is infra-Glacial, it remains to be seen to what Palæolithic period the raised beach belongs. We will proceed to consider the evidence available up to date, commencing with a brief account of the raised beach of North Devon.

I Do not think there is likely to be much gain from a prolonged discussion of this matter, and for the present I shall content myself with a brief recapitulation of the position so far as it affects the views of Dr. P. Marshall on the one hand and of Captain Hutton and myself on the other.

One of the most important and most interesting features of the geology of the Cambridge district is the deposit at Barrington, so widely known for its richness in mammalian remains. This bone-bed has been described many times, and the literature is large. Most of the descriptions, however, confine themselves chiefly to the organic contents, mentioning briefly the character of the larger stones and pebbles, and saying little or nothing about the nature of the finer matrix in which these are embedded.

In the early days of geological investigation it was generally supposed that the soft parts of animals and their more delicate structures could not be found in a fossil state, but modern discoveries have entirely revolutionized our ideas as to what is capable of fossilization.

This complex of igneous rocks lies between Ardlui, at the head of Loch Lomond, and the head of Loch Fyne. In 1892 it was the subject of a fairly exhaustive paper by Teall & Dakyns, but in view of a number of new facts which we have discovered we venture to submit a re-examination of the problems connected with the complex. The mass is broken by a north-east fault. The country to the west of this fault is mainly porphyritic granite and tonalite; to the east there is tonalite and also more basic diorite and ultrabasic rocks. We shall concern ourselves mainly with the basic and ultrabasic groups, as they are somewhat unusual in the “Newer Plutonic Rocks of the Highlands”.