478 



NATURE 



[February 17, 19 10 



Geological Society, January 26. — Prof. W. J. Sollas, 

 F.R.S., president, in the chair.— Dr. A. S. Woodward : 



A skull of Megalosaurus from the Great Oolite of Minchin- 

 hamplon. The specimen was discovered and prepared by 

 Mr. F. Lewis Bradley, and shows, for the first time, the 

 skull of Megalosaurus. It agrees closely with the megalo- 

 saurian skulls of other genera already discovered in the 

 Jurassic and Cretaceous of North America, and resembles 

 Ceratosaurus in possessing a bony horn-core on the nose. 

 As in the jaws of Megalosaurus previously known, the 

 premaxilla of the new specimen bears four teeth ; but these 

 teeth are so different from those of the typical M. huck- 

 landi of the same horizon that they prove the Minchin- 

 hampton fossil to belong to a distinct species. — A. M. 

 Finlayson : Problems of ore-deposition in the lead and 

 zinc veins of Great Britain. Chemical analyses show 

 traces of lead and zinc in several of the rock-formations 

 of Britain, but the ores of the veins are concluded to be 

 derived, not from the country-rock, but from deeper 

 sources, probably in the first place by magmatic segrega- 

 tion. They were transported in the deeper zones by 

 "juvenile" waters, in which fluorine was an important 

 constituent, while in the upper zones, especially in lime- 

 stone districts, underground waters of meteoric origin 

 have played a large part. The vein-solutions carried (i) 

 alkaline sulphides, which held the sulphides of the metals 

 in solution, and (2) alkaline and earthy carbon.ates. The 

 presence of the latter is indicated by the alteration of the 

 wall-rock, which shows a concentration of potash, lime, 

 and carbon dioxide, and a leaching of soda, magnesia, 

 oxides of iron, and silica. In limestones, however, the 

 chief effects of solution on wall-rock were concentration of 

 silica and magnesia. Ore-deposition has persisted over a 

 vertical range of 5000 to 6000 feet, of which more than 

 one-half has been shorn off by denudation. The effects of 

 secondary processes have been exerted to depths of more 

 than 600 feet. — J. VV. Jackson : The vertebrate fauna 

 found in the cave-earth at Dog Holes, Warton Crag 

 (Lancashire). The remains described in this communica- 

 tion were obtained during the systematic investigation by 

 the author of a cave on Warton Crag (west Lancashire) 

 in 1909. The cave, known as Dog' Holes, is situated on 

 the western side of Warton Crag, and opens on a sloping 

 " pavement " of limestone. It owes its origin to the 

 erosion of a series of master-joints in the Carboniferous 

 Limestone. The specimens were derived from the cave- 

 earth below the surface-soil in one of the chambers of 

 the cave. They comprise a large series of small verte- 

 brates, including rodents, Insectivorcs, amphibians, birds, 

 &c. Among the rodents are some interesting forms, the 

 chief of which are the .Arctic and Norwegian lemmings 

 and the northern vole. A large series of non-marine 

 Mollusca was found along with these remains, one species 

 being of particular interest, namelv, Pyramidula ruderata, 

 only known in this country by its fossil remains in Pleisto- 

 cene deposits. The Pleistocene age of the remains is fully 

 discussed, as well as their possible mode of origin through 

 a former swallow-hole. In many respects the cave and 

 its contents bear a striking resemblance to the famous 

 Ightham fissures. 



Zoological Society, February i. — Prof. E. A. Minchin, 

 vice-president, in the chair. — The Hon. P. A. Methuen : 

 A collection of fresh-water Crustacea from the Transvaal. 

 An account of some Entomostraca collected from Lake 

 • Chrissie and other pans or lakes in the Carolina district, 

 which is high veldt country lying near the borders of 

 Swaziland. The paper also gave a short description of the 

 " lie " of the lake, and notes on the geology of the 

 district and the composition of the water. — Dr. J. 

 Pearson : Holothurioidea from the Kerimba Archipelago, 

 Portuguese East Africa, rmd from the Mergui Archipelago, 

 Lower Burma. The collection from the Kerimba Archi- 

 pelago contained twenty-one species, all of which had been 

 previously described. In this paper it is proposed to 

 establish a new genus for the inclusion of Colochiriis 

 violaceus, Th^el. The collection from the Mergui Archi- 

 pelago called for no special comment, none of the fourteen 

 species being new. — Dr. G. S. Brady : A revision of the 

 British species of Ostracoda belonging to the subfamilies 

 Candoninas and Herpctocyphridinac. The p.aper w.is a 

 synopsis intended to show our present knowledge of the 

 NO. 2103, VOL. 82] 



families referred to, describing briefly the known British 

 species. Some few new genera and species, and others 

 already described by foreign authors but not previously 

 recognised as British, were dealt with. — F. E. Beddard : 



The anatomy of Hippopotami^ atnphihius. 



Royal Anthropological Institute, February S — Mr. J. 

 Gray, treasurer, in the chair. — A. L. Lewis : Some 

 dolmens of peculiar types in France and elsewhere. The 

 author described several alUes couvertes in the department 

 of the Oise, in France, which have at one end an open 

 portico or shrine with a round hole 18 inches in diameter 

 opening into the alUe. He then sought to find the monu- 

 ments most nearly resembling them, which appeared to be 

 some of those in the provinces of Bohuslan and \'estergoth- 

 land, in Sweden, described by Dr. Oscar Montelius. The 

 " Giants' Graves " in Sardinia, recorded ninety years ago 

 by Count de la Marmora, and quite recently by Dr. Duncan 

 Mackenzie, had some points in common with them, but 

 they also had quite special features of their own, and it 

 did not appear to the author that there was any real con- 

 nection between the dolmens of the Oise and those of 

 Sweden or Sardinia, as several other kinds of dolmens 

 seemed to bar the way between them. His general con- 

 clusion was that the building of dolmens was not confined 

 to one race and the building of circles to another, nor 

 that there was any one race which originated or diffused 

 both, but rather that megalithic construction was a ph.ise 

 of culture through which many races have passed and 

 which was developed in different ways, not only by separate 

 races, but also, in very restricted areas, by different tribes, 

 without regard to any racial differences or connections 

 between them. — Dr. J. S. Holden : The existence of a 

 Pal.TOolithic bed beneath the glacial Boulder-clay in south- 

 west Suffolk. The implements were discovered in a well 

 sinking at a depth of 100 feet in a seam of unrolled gravels 

 beneath the blue Boulder-clay. The finding of these rude 

 implements 111 51(11 beneath the glacial Boulder-clays is of 

 considerable importance, as they are evidence of the exist- 

 ence of man on this old land surface probably long before 

 the beginning'of the Glacial period. In the discussion, 

 although doubt was expressed as to the artificial character 

 of the implements by some of the speakers, the general 

 opinion was that they were of human workmanship. 



Mathematical Society. February 10.— Sir W. D. Niven, 

 president, in the chair. — H. W. Richmond : Note on 

 double-sixes of lines. — Dr. H. F. Baker : Notes on the 

 theory of functions, (i) On a certain logical principle : 

 (2) on the establishment of the order of a doubly periodic 

 function ; (3) two queries. — Prof. H. Lamb : The diffrac- 

 tion of a solitary wave. 



Edinburgh. 

 Royal ;Society, Tar>uarv 10. -D'. Tanvs linrgefs, vice- 

 president, in the chair. — E. M. Wedderburn : Current 

 measurements in Loch Garry. The measurements were 

 made with an Ekman current meter. The general con- 

 clusions drawn from the Loch Ness observations were 

 confirmed. At the end of the lake the currents were not 

 very uniform, but some very steady currents were observed 

 at the centre. The return current was strongest just above 

 the temperature discontinuity, and at the bottom indica- 

 tions were obtained of currents in the same direction as 

 the wind. The currents were most uniform with moderate 

 and steady winds. In stormy weather they were very 

 variable, both in direction and in velocity. — John 

 McWhan : Observations on some spark-gap phenomena. 

 The paper described a number of curious effects produced 

 by and on sheets of dielectrics interposed in various ways 

 in the path of the electric discharge in air. Many of these 

 depended on the fact that the electrodes were not in the 

 line of the spark. In some the dielectric was perforated, 

 in others it was driven in a definite direction with or with- 

 out rotation, as the case might be, and in other cases the 

 accompanying luminous effects with the brush discharge 

 were very remarkable. The phenomena could not be co- 

 ordinated on any of the ordinarily accepted theories. — 

 Dr. G. A. Carse and D. MacOwan : Earth-air electric 

 current and atmospheric potential gradient near Edinburgh. 

 The observations were made with Wilson's portable 

 electrometer. The values of the earth-air current in the 

 town werS found to be about one-tenth of those got by 



