May 31, 1900] 



NATURE 



119 



of the experiments have been plotted synoptically on a curve, 

 and the several lines have been drawn upon which these points 

 should lie, according to the various theories. It is readily seen 

 that the points cluster round the line which represents the 

 existence of a specific shearing stress. The author, therefore, 

 favours the existence of this stress for any material. The chair- 

 man read a communication upon the subject from Dr. Chree. 

 Mr. Guest, in his paper, has regarded the shearing stress theory 

 as a little known one. As the shearing stress is half the differ- 

 ence between the greatest and least principal stresses, this theory 

 is the same as Prof. G. H. Darwin's maximum stress-difference 

 theory. All the theories suppose that the stress-strain law is 

 linear, and that strains are so small that their squares and pro- 

 ducts can be neglected. Mr. Guest concludes that in ordinary 

 materials the law is linear to the elastic limit, which answers to 

 a stress lower than that which answers to the yield point, and 

 that yield point phenomena arise between these. Nevertheless, 

 he focusses attention on the yield point as the criterion of strength, 

 and assumes that Hooke's law holds up to it. 



Entomological Society, May 2. — Mr. W. L. Distant, 

 Vice-President, in the chair. — Mr. W. L. Distant exhibited the 

 cocoon, measuring nearly three and a half inches each way, of 

 a Coprid beetle — probably belonging to the genus Heliocopris — 

 found at Pretoria in the Transvaal.— The Rev. Theodore Wood 

 «;xhibited a specimen of Carabus auratus, L. , taken in either June 

 or September 1898 by Mr. Ferrand, of Littlefield House, 

 Exmouth, on the Haldon Hills in the neighbourhood of that 

 town. — Mr. McLachlan exhibited an example of Rhinocyphea 

 fulgidipennis, Guerin, a brilliant little dragon-fly of the sub- 

 family Calopteryginae, a native of Cochin China, which, so far 

 as he knew, had not been captured since prior to 1830. It had 

 been in M. Guerin's hands, and Mr. McLachlan had received 

 it from M. Rene Oberthtir. — Mr. T. A. Chapman exhibited 

 various specimens illustrating Acaiithopsyche opacella. — Mr. 

 Barrett exhibited specimens of Heterocera destructive to the 

 fruit crops of South Africa. Among them Sphingomorpha 

 iitoiiteironis, Butl., known as the Fruit Moth in Cape Colony — 

 a bold and powerful insect, with a sucking tongue strong enough 

 to pierce the sound skin of a peach or fig. The presence of a 

 light does not appear to disturb it, so that examination of its 

 methods can be readily made, when it can be seen that it does 

 not lake advantage of the natural opening into a fig, or of a 

 crack or other injury to a peach, but deliberately pierces a hole 

 which afterwards shows as a small round spot, from which 

 decay invariably results. It seems a matter of indifference to 

 the moth whether the fruit has fallen, or is on the tree, ripe or 

 unripe. With regard to Achaea lienardi and Serrodes inara, 

 the two species are restless and timid, and therefore more 

 difficult to observe. In the present season, however, both have 

 been extremely abundant, and have been seen at apparently 

 uninjured fruit, so that it seems they are capable of equal 

 destruction. Several others, feeding mainly on damaged fruit, 

 were also taken with the aforesaid species, among them some 

 new to science, and recently described by Sir George Hampson. 

 Mr. Jacoby exhibited Callomorpha wahlbergi from Africa, and 

 Spilopyra sumptuosa irom Australia. — A paper was communi- 

 ,cated on "New Paltearctic Pyralidii?," by Sir George F. 

 jHampson, Bart. 



Anthropological Institute, May 15. — Mr. C. H. Read, 

 President, in the chair.— The president alluded to the severe 

 )ss which the Institute and anthropology in general had sus- 

 lined in the loss of its former president, the late General Pitt- 

 Livers. — Mr. F. Haverfield contributed a note on certain stone 

 »bjects discovered on a Roman site at Clanville, in Hants, and 

 . discussion ensued from which it appeared improbable that they 

 irere of human workmanship. — Mr. J. Allen Brown described a 

 >llection of stone implements brought from Pitcairn Island 

 y Lieut. Pike, R.N. The implements are of two types, both 

 jrmed of the volcanic rocks of the island. The first series con- 

 ^ts of stone axes of analogous forms to those of other islands of 

 "le Pacific. The other is peculiar, being large, and with in- 

 »rved sides and broad cutting edge, more or less ground as 

 rell as chipped. A third form is that of a cylindrical chisel, 

 "he author mentioned also the discovery of rock carvings of sun, 

 loon, birds, &c., tombs with pottery and human skulls, and of 

 irved stone figures like those of Easter Island. The fact that 

 le implements were found below the surface of the ground, and 

 liat from the time of its discovery by Carteret until its occupa- 

 'on by the mutineers of the Bounty, makes it probable that the 

 smains in question are of considerable age.— Mr. H. Stopes 



NO. 1596, VOL. 62] 



exhibited a number of unclassified stone objects which he had 

 collected from the river gravels of the Thames valley, and dis- 

 cussed the purposes for which he believed them to have been 

 shaped. He also produced specimens of Neritina flaviatilis 

 found in the same gravels, which he regarded as an indication of 

 their age. 



Zoological Society, May 22,— Dr.jAlbert Gunther, F.R.S., 

 Vice President, in the chair. — A communication was read from 

 Prof. G. B. Howes, F.R.S., and Mr. H. H. Swinnerton, on 

 the development of the skeleton of the Tuatera, Sphencdon 

 {Hatleria) piinctattis, which was stated to be the outcome of 

 eighteen months' work on materials supplied to the authors by 

 Prof. Dendy, of Christchurch, N.Z An account was given of 

 the egg, the hatching, and the habits of the hatched young, 

 which the authors reared till four months old. — The Mala- 

 costracan Crustacea collected by Mr. Rupert Vallentin at the 

 Falkland Islands, from December 1898 to February 1899, 

 formed the subject of a paper by the Rev. T. R. R. Stebbing, 

 F.R.S. Many of the species had long been known, as several 

 scientific expeditions had been made to these islands during this 

 century. This carefully made collection, however, had afforded 

 a much needed opportunity for discussing and clearihg up 

 obscure points in some of the earlier descriptions of the 

 Crustacean fauna. — Mr. L. A. Borradaile read the fourth instal- 

 ment of his memoir on Crustaceans from the South Pacific. 

 This part contained an account of the crabs, of which 77 

 species were enumerated. Seven new species were described, 

 and a scheme of classification of the swimming crabs 

 (Poriunidae) was put forward. — A communication was read 

 from Dr. R. Bowdler Sharpe. which contained an enumeration of 

 the birds — 56 species in all — collected during the Mackinder 

 Expedition to Mount Kenya, accompanied by field-notes of the 

 collectors. — Mr. F. E. Beddard, F.R.S., read a paper, entitled 

 " A Revision of the Earthworm Genus AinyntasJ' According 

 to the author, this genus comprised 102 species, which were 

 enumerated and commented upon. — Mr. Beddard also read a 

 paper on the structure of a new species of earthworm, which he 

 proposed to name Benhamia bttdgetti, after its discoverer, Mr. 

 J. S. Budgett, who had obtained two specimens of it at 

 McCarthy's Island during his recent visit to the Gambia. 

 Paris. 

 Academy of Sciences, May 21. — M. Maurice Levy in the 

 chair. — Researches on the formation of nitric acid during com- 

 bustions, by M. Berthelot. The compressed oxygen used in 

 combustions in the calorimetric bomb always contains a small 

 quantity of nitrogen, up to 8 per cent. A portion of this is 

 oxidised during the combustion, and the amount of nitric acid so 

 formed has been regularly measured in order to correct the 

 calorimetric data. The author now attempts to trace the 

 relation between the nature of the organic substance under com- 

 bustion and the quantity of nitric acid formed, details being 

 given in the present paper of experiments on amorphous carbon, 

 graphite and diamond. — Limits of combustibility by red-hot 

 copper oxide of hydrogen and methane diluted with large 

 volumes of air, by M. Armand Gautier. When combustible 

 gases, such as hydrogen or marsh gas, are mixed with large 

 quantities of air and are passed over columns of red-hot 

 copper oxide, the difficulty of completely burning the gas 

 increases with the dilution. Thus with a dilution of 20 parts 

 in 100,000, hydrogen is not completely burnt on passing over 

 a column of 35 centimetres of red-hot copper oxide, but com- 

 bustion is complete when this length is doubled. Methane is 

 more difficult to burn ; thus at a dilution of 7 in 100,000 nearly 

 half the carbon escaped unburnt after passing over a column of 

 oxide 70 cm. long. — Publications of the Observatory of Besan9on 

 from 1886 to 1896, .by M. Lawy. — Action of hydrogen bromide 

 upon dextro-rotatory benzylidene camphor, by MM. A. Haller 

 and J. Minguin. Benzylidene camphor combines with hydro- 

 bromic acid to form mono-bromo-benzyl-camphor. If the 

 combination is carried out at 100°, two other products are ob- 

 tained, benzylidene-campholic acid, 



(COOH).C8Hi4.CH:CH.C6H5, 

 and phenyloxy-homocampholic acid, 



(COOH).C8Hi4.CH.^.CH(OH)CaH3, 

 derivatives of which are described. — On fossil forests and the 

 vegetative soils of the coal-measures, by M. Grand'Eury. 

 Further arguments in favour of the author's view that the 

 vegetable fossils have really grown in the places where they 

 now occur, and have not been deposited there by water. — 



