February 23, 1893] 



NATURE 



407 



Geological Society, January 25. — W. H. Hudleston, 

 F.R.S., President, in the chair. — The following communications 

 were read ; On inclusions of tertiary granite in the Gabbro of 

 the Cuilin Hills, Skye ; and on the products resulting from 

 the partial fusion of the acid by the basic rock, by Prof. J. 

 W. Judd, F.R.S. — Anthracite and bituminous coal-beds; 

 an attempt to throw some light upon the manner in which 

 anthracite was formed ; or contributions towards the controversy 

 regarding the formation of anthracite, by W. S. Gresley. 



February 8. — W. H. Hudleston, F.R.S., President, in the 

 chair.— The following communnications were read : Notes on 

 some coast -sections at the Lizard. By Howard Fox and J. J. 

 H. Teall, F.R.S. In the first part of the paper the authors 

 describe a small portion of the west coast near Ogo Dour, where 

 hornblende-schist and serpentine are exposed. As a result of 

 the detailed mapping of the sloping face of the cliff, coupled 

 with a microscopic examination of the rocks, they have arrived 

 at the conclusion that the serpentine is part and parcel of the 

 foliated series to which the hornblende-schists belong, and that 

 the apparent evidences of intrusion of serpentine into schist in 

 that district are consequences of the folding and faulting to which 

 the rocks have been subjected since the banding was produced. 

 The interlamination of serpentine and schist is described, and 

 also the effects of folding and faulting. Basic dykes, cutting 

 both serpentine and schists, are clearly represented in the portion 

 of the coast which has been mapped, and these locally pass into 

 hornblende-schists, which can, however, be clearly distinguished 

 from the schist'^ of the country. The origin of the foliation in 

 the dykes is discussed. The second part of the paper deals with 

 a small portion of the coast east of the Lion Rock, Kynance. 

 Here a small portion of the "granulitic series" is seen in juxta- 

 position with serpentine. The phenomena appear to indicate 

 that the granulitic complex was intruded into the serpentine ; 

 but they may possibly be due to the fact that the two sets of 

 rocks have been folded together while the granulitic complex 

 was in a plastic condition, or to the intrusion of the serpentine 

 into the complex while the latter was plastic. — On a radiolarian 

 chert from Mullion Island, by Howard Fox and J. J. H. Teall. 

 The main mass of Mullion Island is composed of a fine-grained 

 *' greenstone," which shows a peculiar globular or ellipsoidal 

 structure, due to the presence of numerous curvilinear joints. 

 Flat surfaces of this rock, such as are exposed in many places 

 at the base of the cliff, remind one somewhat of the appearance 

 of a lava of the " pahoehoe " type. The stratified rocks, which 

 form only a very small portion of the island, consist of cherts, 

 shales, and limestone. They occur as thin strips or sheets, and 

 sometimes as detached lenticles within the igneous mass. The 

 chert occurs in bands varying from a quarter of an inch to several 

 inches in thickness, and is of radiolarian origin. The radiolaria 

 are often clearly recognisable on the weathered surfaces of some 

 of the beads, and the reticulated nature of the test may be 

 observed by simply placing a portion of the weathered surface 

 under the microscope. The authors describe the relations 

 between the sedimentary and igneous rocks, and suggest that 

 the peculiar phenomena may be due either to the injection of 

 igneous material between the layers of the stratified series near 

 the surface of the sea-bed while deposition was going on, or 

 possibly to the flow of a submarine lava. The form of the 

 radiolaria observed in the deposit, and also their mode of pre- 

 servation, are described in an appendix by Dr. G. J. Hinde. — 

 The reading of these papers was followed by a discussion, in 

 which the President, Rev. Edwin Hill, Prof. Bonney, Dr. 

 Hicks, Dr. Hind, and the authors took part. — Note on a radio- 

 larian rock from Fanny Bay, Port Darwin, Australia, by G. J. 

 Hinde. A specimen brought from Fanny Bay by Captain 

 Moore, of H.M.S. Penguin, is of a dull white or yellowish 

 tint, in places stained red. It has an earthy aspect, and is some- 

 what harder than chalk, but gives no action with hydrochloric 

 acid. Microscopic sections show a fairly transparent grounduiass, 

 apparently amorphous silica, containing granules and subangular 

 fragments up to '075 millim. in diameter, some of which appear 

 to be quartz. Besides this, the rock contains numerous rafliularia, 

 and it is really a radiolarian earth intermediate in character 

 between the Barbados earth and such cherts as those of the 

 Ordovician strata of Southern Scotland. The details of the 

 extent of the deposit and its relationship to other rocks of the 

 area are not yet obtainable, though it is possible that a con- 

 siderable thickness of rock mentioned by Mr. Tenison Woods as 

 occurring in this area may also be of radiolarian origin. The 

 author describes a species of Cenellipsis, two of Astrophacus, 



one of Ltikoc_yc/ia{nev/), one q{ Aviphibrachium, three olSpongo- 

 discus (one new), four of Spongolena (all new), two of Dictyo- 

 mitra (both new), one of Lithocavipe (new), and two of 

 Stichocapsa (both new). From these it is not practicable at 

 present to determine the geological horizon of the rock ; with 

 one exception, all the genera represented occur from Palaeozoic 

 times to the present. — Notes on the geology of the district west 

 of Caermarthen. Compiled from the notes of the late T. Roberts 

 (communicated by Prof. T. McKenny Hughes, F.R.S.). To 

 the east of the district around Haverfordwest, formerly described 

 by the author and another, an anticlinal is found extending towards 

 Caermarthen, The lowest beds discovered in this anticline are 

 the Teiragrapius-beds of Arenig age, which have not hitherto 

 been detected south of the St. David's area. They have yieldtd 

 eight forms of graptolite, which have been determined by Prof. 

 Lapworth. The higher beds correspond with those previously 

 noticed in the district to the west ; they are, in ascending order : 

 (i) Beds with "tuning-fork " Didymograpti, (2) Llandeilo lime- 

 stone, (3) Dicranograptus-%h3.\GS, (4) Kobeston Wathen and 

 Sholeshook limestones. Details of the geographical distribution 

 of these and of their lithological and palceonlological characters 

 are given in the paper. After the reading of this paper Dr. 

 Hicks said he felt i-ure he was expressing the feelings of the 

 Fellows in referring to the serious loss which the Society had 

 suffered by the death of Mr. T. Roberts, who certainly was one 

 of the most promising palaeontologists in this country. The 

 important researches which he carried on, in conjunction with 

 Mr. Marr, had made is now comparatively easy to understand 

 some intricate and extensive districts in Pembrokeshire and 

 Caermarthenshire, which previously were little more than blanks 

 on the geological map. 



February 17. — Anniversary Meeting. — The medals and 

 funds were awarded as follows : — The WoUaston medal to 

 Prof. N. S. Maskelyne, F.R.S.; Murchison medal to the 

 Rev. O. Fisher ; Lyell medal to Mr. E. T. Newton ; and the 

 Bigsby medal to Prof. W. J. Sollas, F.R.S.'; the balance 

 of the proceeds of the Wollaston fund to Mr. J. G. Good- 

 child ; that of the Murchison fund to Mr. G. J. Williams ; 

 and that of the Lyell fund to Miss C. A. Raisin and Mr. A. N. 

 Leeds. The following is the list of officers and council elected 

 at the meeting :— President : W. H. Hudleston, F.R.S. Vice- 

 Presidents : Sir A. Geikie, F.R.S., G. J. Hinde, Prof. J. 

 W. Judd, F.R.S., H. Woodward, F.R.S. Secretaries : J. E. 

 Marr, F.R.S., J. J. H. Teall, F.R.S. Foreign Secretary: J. 

 W. Hulke, F.R.S. Treasurer: Prof. T. Wiltshire. Prof. J. 

 F. Blake, Prof. T. G. Bonney, F.R.S., R. Etheridge, F.R.S., 

 Sir A. Geikie, F.R.S., Prof. A. H. Green, F.R.S., Alfred 

 Harker, H. Hicks, F.R.S., G. J. Hinde, T. V. Holmes, W. 

 H. Hudleston, F.R.S., J. W. Hulke, F.R.S., Prof. J. W. 

 Judd, F.R.S., R. Lydekker, Lieut. -General C. A, McMahon, 

 J. E. Marr, F.R.S., H. W. Monckton, Clement Heid, F. Rut- 

 ley, J. J. H. Teall, F.R.S., Prof. T. Wiltshire, Rev. H. H. 

 Win wood, H. Woodward, F.R.S., H. B. Woodward. The 

 presidential address dealt with some recent work of the Geolo- 

 gical Society, the subjects ranging over a period of six or seven 

 years. These embraced Pleistocene geology, theories in connec- 

 tion with Glaciation, Tertiary, Cretaceous, Jurassic, and Permo- 

 Triassic geology. It further mentions that the number of papers 

 on Pleistocene geology has been very considerable, and many of 

 them relate to the south-east and the south of England ; those 

 relating to Central England and South Wales were fewer in 

 number, whilst the north had furnished but few papers. The 

 great memoir on the Westleton Beds had provided much mat- 

 erial for consideration ; that portion relating to the Southern 

 Drift being especially interesting. Reference was made to a 

 paper on Pleistocene succession in the Trent basin as forming a 

 fitting introduction to the fascinating problems connected with 

 the North Wales border on the one side and with Flamborough 

 Head on the other. From Scotland notice was taken of some 

 supplementary remarks on the paralled roads of Glen Roy. 

 Speculation as to the evidence of a palaeozoic ice age, 

 the date and duration of the Pleistocene glacial period, 

 and a notice on misconceptions regarding the evidence of 

 former glacial periods were also discussed. The Tertiary 

 Geology of the London and Hampshire basins was considered, 

 more especially in relaiion to the Upper Eocene, or 

 Bartons, and their probable equivalents in West Surrey. 

 Under this heading, also, comes the Geology of Barbados, 

 since the oceanic deposits in that island were held to be of late 

 Tertiary age. These interesting discoveries were reviewed 



NO. 12 17, VOL. 47] 



