502 



NATURE 



[March 23, 189^ 



rock. Wilh the exception of very rare boulders of quartz, the 

 hill and valley-gravels of the greater part of Kent, Surrey, and 

 Berkshire are entirely free from these materials. The author 

 points out that the river Thames is not, however, the actual 

 southern boundary of the distribution of these glacial drift 

 pebbles and boulders, though the number of localities where 

 they are found in gravels south of that river is few. The author 

 describes or mentions several, of which the following are the 

 mobt important : — Tilehurst, Reading, Sonning, Bisham at 351 

 feet above the sea, Maidenhead, Kingston, Wimbledon, and 

 Dartford Heath. — On the plateau-gravel south of Reading, by 

 O. A. Shrubsole. This paper contains observations on the 

 gravel of the Easthampstead-Yately plateau. The constituent 

 elements of the gravel are described, and the author notes 

 pebbles of non-local material near Caesar's Camp, Easthamp- 

 stead, on the Finchampstead Ridges, and at Gallows Tree Pit 

 at the summit of the Chobham Ridges plateau. He mentions 

 instances of stones from the gravel of the plateau (described in 

 the paper) which may bear marks of human workmanship. He 

 furthermore argues that the inclusion of pebbles of non-local 

 origin in the gravels may be due to submergence of the plateau 

 up to a height of at least 400 feet above present sea-level, and 

 cites other facts in support of this suggestion. He concludes 

 that the precise age of the gravel can only be more or less of a 

 guess, until the mode of its formation has been definitely ascer- 

 tained. The reading of these papers was followed by a 

 discussion, in which the President, Dr. Hicks, Mr. J. A. Brown, 

 Prof. J. F. Blake, Mr. W. J. L. Abbott, Mr. Herries, Mr. 

 Monckton, and Mr. Shrubsole took part. — A fossiliferous 

 pleistocene deposit at Stone, on the Hampshire Coast, by 

 Clement Reid. (Communicated by permission of the Director- 

 General of the Geological Survey.) This is practically a supple- 

 ment to a paper on the pleistocene deposits of the Sussex 

 coast, that appeared in the last volume of the Quarterly 

 Journal. An equivalent of the mud-deposit of Selsey has now 

 been discovered about twenty miles farther west, and from it 

 have been obtained elephant-remains, and some mollusca and 

 plants like those found at Selsey. Among the plants is a South 

 European maple. Some remarks were made on the paper by 

 the President, Dr. Hicks, and Mr. W. J. L. Abbott, and the 

 author replied. 



Zoological Society, March 14.— Sir W. H. Fowler, F.R.S., 

 President, in the chair, — The Secretary read a report on the 

 additions that had been made to the Society's menagerie during 

 the month of February, 1893, and called attention to two terrapins 

 procured on Okinawa Shima or Great Loochoo Island by Mr. 

 P, A. Hoist, and kindly presented by that gentleman. Mr. 

 Boulenger had determined these tortoises as being Spengler's 

 terrapin {Nicoria spengleri). — Mr. O. Thomas exhibited and 

 made remarks on a rare antelope (Nanotragus livingstonianus) 

 from Northern Zululand. — Dr. Forsyth-Major exhibited and 

 made remarks on a tooth of Orycteropus from the Upper Miocene 

 of Maragha, Persia, which he referred to O. gaiidryi, of the 

 Upper Miocene of Samos. Drawings of the remains of the 

 latter were exhibited, as well as a photograph of a femur of a 

 struthious bird from the same deposit in Samos. The habitats 

 of Siruthio and Orycteropus were thus shown to have been 

 essentially identical m past times, as in the present. Therefore 

 the general conclusions to be drawn from their geographical 

 distribution would apply equally to both. — Mr. Old field Thomas 

 made some suggestions for the more definite use of the word 

 ' ' type " and its compounds, as denoting specimens of a greater or 

 less degree of authenticity. — Mr. P. L. Sclater, F.R.S., pointed 

 out the characters of a new African monkey of the genus 

 Cercopithecus ; and took the opportunity of giving a list of the 

 species of this genus known to him, altogether 31 in number, 

 together with remarks on their exact localities. — Prof. F. 

 Jeffrey Bell read a paper on Odontaster and the allied and 

 synonymous genera of the Asteroidea. — Mr. A. D. Michael read 

 a paper upon a new species (and genus) of Acarus found in 

 Cornwall. The creature in question, which it was proposed to 

 call Lentuttgula algivorans, was found in some quantity on a 

 green alga {Cladophora fractd) near the Land's End. It was 

 a minute creature belonging to the family Tyroglyphidoe, the 

 remarkable feature about it being that, whereas the two hind 

 pairs of legs were terminated by a hard and powerful single 

 claw (which claw sprang from the end of the tarsus), the two 

 front pairs had the tarsus itself hardened and curved strongly 

 downward, forming clinging- and walking-organs ; while from 



NO. I 22 I, VOL. 47] 



the side of the tarsus sprang a long peduncle, flexible in all 

 directions at the will of the creature, and bearing an exceedingly 

 minute claw. This apparatus was not used in climbing, but 

 had become wholly tactile. Such an arrangement was previously 

 unknown in the Acarina. — Prof. Howes described some abnor- 

 mal vertebrae of certain Ranidae {Rana catesbiana, R. esculenta, 

 and R. macrodon) in which the so-called "atlas" possessed 

 transverse processes and trans-atlantal nerves. Prof. Howes 

 discussed the bearings of these specimens on the morphology of 

 the parts, deducing the argument that the first vertebra of the 

 Amphibia is probably to be regarded as a representative of at 

 least two vertebrae, of which the formative blastema has become 

 merged in the occiput in the Amniota. The author also described 

 a stage in the development of the urostyle of Pelobates, and 

 showed that, in this Batrachian, there is a provisional inversion 

 in the order of development of the parts of the urostyle and 

 precoccygeal vertebrae. He also described a reduced hind limb 

 oi Salamandra 7tiaculosa, in which the reduction and fusion of 

 the parts remaining realised the condition normal for the Urodele 

 limb with numerically reduced digits. 



Royal Meteorological Society, March 15.— Dr. C. Theo- 

 dore Williams, President, in the chair.— Mr. Shelford Bidwell, 

 F. R. S., delivered a lecture on some meteorological prob- 

 lems, which was illustrated with numerous photographs and 

 experiments. The lecturer said that one of the oldest and still 

 unsolved problems of meteorology relates to the origin of atmo- 

 spheric electricity. Many possible sources have been suggested, 

 among them being the evaporation of water and the friction of 

 dust-laden air against the earth's surface. Having granted some 

 sufficient source of electrification, Mr. Bidwell said that it is 

 not difficult to account for the ordinary phenomena of thunder- 

 storms. Photography has shown that the lightning flash of the 

 artists, formed of a number of perfectly straight lines arranged 

 in a zig zag, has no resemblance to anything in nature. The 

 normal or typical flash is like the ordinary spark discharge of 

 an electrical machine, it follows a sinuous course, strikingly simi- 

 lar to that of a river as shown upon a map. The several varia- 

 tions from the normal type all have their counterparts in the 

 forms taken by the machine spark under different conditions, 

 and the known properties of these artificial discharges may be 

 assumed to afford some indication as to the nature of the cor- 

 responding natural flashes. Thus, for example, the ramified or 

 branched flash, from which no doubt the dreaded " fork light- 

 ning " derives its name, is probably one of the most harmless 

 forms of discharge. Ever since the time of Franklin it has been 

 customary to employ lightning rods for the protection of import- 

 ant buildings. According to Dr. Oliver Lodge these are of no use 

 in the case of an " impulsive rush" discharge, which, however, is 

 of comparatively rare occurrence. Lightning conductors, how- 

 ever well constructed, cannot therefore be depended upon to 

 afford perfect immunity from risk, Mr. Preece is of opinion that 

 the "impulsive rush," though easily producible in the laboratory, 

 never occurs in nature, Mr. Bidwell made some remarks as to 

 the duration of a lightning flash and the causes of its proverbial 

 quiver, and suggested an explanation of the characteristic dark- 

 ness of thunder clouds, and of the large rain-drops which fall 

 during a thunder shower. The lecturer concluded with some 

 observations concerning the probable cause of sunset colours, 

 which he attributed to the presence of minute particles of dust 

 in the air. 



Oxford, 



University Junior Scientific Club, March i.— The 

 President in the chair, — Mr. C. H. H, Walker exhibited 

 some compounds of the rare metals from the collection of the 

 late Duke of Marlborough, which had been presented to the 

 University by the Duchess, — Among the papers read was one 

 by Dr. Leonard Hill on cortical localisation. 



March 10. — The President in the chair. — -Adjourned discussion 

 on Dr. L. E. Hill's paper on cortical localisation. 



Cambridge. 

 Philosophical Society, February 27.— Prof. T, McK. 

 Hughes, President, in the chair. — The following communica- 

 tions were made to the Society : — On the histology of the 

 blood of rabbits which have been rendered immune to anthrax, 

 by Lim Boon Keng. The research was conducted in the patho- 

 logical laboratory of the University. The rabbits were rendered 



