It is admitted that the data, from which the author draws his conclusions are, taken piecemeal, scanty, hazy, and often ambiguous. The main purpose of the investigation was to examine the contention of Bonney that the phenomena of Bardon Hill might possibly be explained by assuming flow-brecciation, and also to satisfy the author's own observation of a not irregular distribution of enclaves, which seemed to him to warrant a revision of the ideas held on the relative age of the units, that go to the building of the hill. Perhaps the main quest may be summarized into—whether the Bardon Rock is to be regarded as merely compacted agglomerate or whether it is truly igneous ? With these purposes in view the groups of data given in this paper rank in order of value: 1, Field Data; 2, Macroscopic Data; 3, Microscopic Data; 4, Chemical Data. This order iolds good, because the more searching the investigation the more obscure the real issues become—befogged by the increasing insistence of metamorphic phenomena. Any conclusions drawn must satisfactorily explain the bulk phenomena of the Bardon Hill rocks and must depend on converging evidence. Where two opposing explanations are possible, the author has adopted the simpler as the more likely.

The island of Sark lies 7 miles to the east of Guernsey. Its length from north to south is over 3 miles, and its average breadth is one and a half miles. The island is a table-land with an average height, above sea-level, of 300 feet, probably a result of marine planation of Pliocene date. Access is accomplished by scaling the cliffs of Havre Gosselin (west coast) or through the tunnel of Creux Harbour (east coast). The southern portion, Little Sark, joins the mainland by an isthmus 8 feet wide, 250 feet high, and 300 yards long, known as La Coup´ee. Here, as in many parts of the island, the cliffs drop sheer to the sea, and considerable care is required in examining the rocks.

In the bilateral symmetry of the Rugose corals it is the general form of the polyparium, presenting a cone bent in the form of an oxen horn, that strikes at once the observer's eye and obliges him to seek for an explanation.

The sand described in the following notes was dredged from the mid-channel of the river at the following places:—Swale Nab, Dunsforth, Aldwark Bridge, below Linton Lock, and Beningbrough. Two samples were also obtained from the Nidd at points 100 and 200 yards respectively from its confluence with the Ouse. For comparative purposes sand from the banks and alluvial flat of the Swale above Ainderby Steeple is likewise included.

In April, 1925, while mapping the coastal plain of the Red Sea south of Berenice for the Egyptian Government, I came across a remarkable example of columnar structure in sandstone, an illustration of which is shown in the accompanying photograph.

I have been asked by Professor Gregory to examine and describe two pebbles which he has collected from the pre-glacial gravel of Little Hayes, in the Crouch Valley, South-East Essex. Examined in thin section under the microscope, one of these pebbles agrees very well with the typical chert of Arngrove (Bucks) and Studley (Oxon) in size of spicules, their mineralization, their number in a given field, and the proportion of angular sand-grains.

The rarity of drifts in the Crouch Valley has been often remarked. The only river gravel marked in it on the Geological Survey Map, sheet I N.E., is a small patch at Little Hayes, a couple of hundred yards north of the Crouch, and 1¼ miles S.S.W. from Woodham Ferrers railway station. In the Evolution of the Essex Rivers (1922, p. 47), an analysis of the five chief constituents, based on a collection made by Mr. H. J. Nicholson, recorded some Jurassic sandstones which I regarded as probably derived from the boulder clay on hills about three miles north and north-west. A visit to the pit last year in order to obtain larger specimens of the Jurassic material yielded various cherts; one is a typical Rhaxella chert, which has not been previously recorded so far to the south-east. A thin bedded oolitic chert, which was different to any that I knew, was submitted to Mr. H. C. Sargent with the inquiry whether it might be one of the Carboniferous cherts of the Midlands. Mr. Sargent identified some of the inclusions as silicified oolitic grains, and rejected the rock as Midland Carboniferous. The specimens and slides were also kindly examined by Professor Boswell, who showed them to Mr. E. T. Dumble for comparison with the Rhaxella chert found by him in the Crag; they also did not know any similar rock. The specimens were then sent to Dr. Morley Davies, who confirmed the identity of the one specimen with the ordinary Oxford-Buckingham Rhaxella chert, and has, in the previous note, described the other as a Rhaxella chert in which the spicules are the nuclei of oolitic grains.

The subject matter of the present note is furnished by the abnormal redness of many parts of the Arran Carboniferous. W. Gunn, in his invaluable memoir, records this colouration without particular comment; but, as Scottish geologists are aware, B. N. Peach, under whose supervision Gunn carried out his survey, has long claimed that the Arran Carboniferous is stained by solutions that have percolated down from overlying New Red Sandstone. After a careful consideration of the exposures, I feel convinced that two features of Peach's proposition are secure:—

(1) The red colour of much of the Arran Carboniferous is not original.

(2) It must be in some way connected with the New Red Sandstone.

The following remarks have been suggested by the perusal of Mr. E. B. Bailey's draft of his paper on the “Subterranean Penetration by a Desert Climate”.