May 19, 1892] 



NA TURE 



69 



nized as new by Maximowicz, are described : Genliana Maxi- 

 mowiczi, leticonielccna, pwpurata, sip'ionantha. Resell, glo- 

 merata, and G. K'/troo, var. bretddens. They are from 

 Central Asia, North China, and Mongolia. — Report of the 

 International Meteorological and Polar Conferences, and the In- 

 ternational Committee of Weights and Measures, by H. Wild. 

 No. 4 : Remarks on Mr. Kock's work, " Comicorum Atticorum 

 fragmenta" (in German). 



SOCIETIES AND ACADEMIES. 

 London. 



Royal Society, May 5.—" Transmission of Sunlight 

 through the Earth's Atmosphere. Part II. Scattering at 

 Different Altitudes." By Captain W. de W. Abney, C.B,, 

 D.C.L., F.R.S. 



In this paper the results of observations made by exposing 

 platinotype paper are recorded, and it is shown that the total 

 intensity of light as thus registered is the same as if observa- 

 tions had been made on a ray of \ 4240 alone. The observa- 

 tions were made at altitudes varying from sea-level to 12,000 

 feet in different countries, at different times of the year, and 

 during four to five years. The instrument in which the ex- 

 posures were made is described, as also the method of deriving 

 the intensity of light from the developed prints. The results of 

 these observations agree closely with those obtained by the 

 measures of the spectrum which was described in Part I. of this 



subject. The value of k in the formula (i) I' — C^^' -'' 

 (from which can be calculated the loss of intensity of a ray of 

 any particular wave-length) was found to be o '00146 at sea- 

 level. It was also found that k apparently varied as It"-, h being 

 the barometric pressure. A table is attached, showing the 

 value of the transmitted light in the formula (2) I' = la.r, where 

 a is a constant and x the air thickness in terms of the vertical 

 thickness, ft. being the formula I' = le"'*'^, from which (i) and 

 (2) are both shown to be derived. 



Linnean Society, April 21. — Prof. Stewart, President, in the 

 chair.— An example of an Australian bird (Gymnorhina), which 

 had lately been shot near Tor Abbey, Devonshire, after being 

 observed all the winter, and which had doubtless escaped from 

 confinement, was exhibited on behalf of Mr. W. Else, Curator of 

 the Torquay Museum.— On behalf of Mr. Charles Head, of 

 Scarborough, two specimens of the Whiskered Bat ( Vespertilio 

 mvstacinus) taken in that neighbourhood were exhibited.— Mr. 

 W. B. Hemsley, F. R.S., read a paper entitled " Observations on 

 a Botanical Collection made by Mr. A. E, Pratt in Western 

 China, with descriptions of some new Chinese plants from 

 various collections." Mr, Pratt travelled in 1889-90 in Western 

 China, close on the borders of Eastern Tibet, and though chiefly 

 in search of zoological specimens, he fortunately secured the 

 services of a native who had been trained to dry plants by Dr. 

 Henry, the result being that he was enabled to bring home a 

 very interesting botanical collection. The plants were obtained 

 chiefly at elevations of 9000 to 13,500 feet, in the neighbour- 

 hood of Tat-sien-lu, a frontier town situated in about 30 N. lat. 

 and 1020 15' E. long. ; and although Mr. Hemsley reported that 

 he had not finished working out the collection, he estimated that 

 it contained about 500 species, of which perhaps 150 species were 

 new to science. The paper was criticized by Mr. C. B. Clarke, 

 who remarked that the mountain ranges of Western China 

 seemed to abound in showy herbaceous plants, rivalling in this 

 respect the richest districts of the Himalayan region, of which, 

 in fact, it is a continuation.— Mr. H. M. Bernard then gave an 



NO. II 77, VOL. 46] 



abstract of a paper on the relation of the Acaridae to the 

 Arachnida, in which he argued that the former were fixed 

 larval forms of the latter ; though he found a difficulty in 

 dealing with the segmentation, this being so profoundly modi- 

 fied and in some cases lost. The paper was criticized by Mr. 

 A. D. Michael, Mr. Breeze, and Prof. G. B. Howes, all of 

 whom, while testifying to the ingenuity of Mr. Bernard's 

 reasoning, considered that there was hardly as yet sufficient 

 evidence to justify the acceptance of his conclusions. 



May 5. — Prof. Stewart, President, in the chair.— On behalf 

 of Mr. Holt, Prof. G. B. Howes exhibited and made re- 

 marks on a very interesting collection of the metamorphosing 

 larvae of flat-fish. — Mr. Curtis showed a photograph of sec- 

 tions of the Silver and Douglas firs, illustrating the relative 

 rate of growth in trees of the same age growing in the same 

 soil and under similar conditions in all respects, the diameter 

 of the one {A. Douglasii) being nearly double that of the other. 

 — Mr. George Murray exhibited spirit specimens of Asco- 

 thamnion intricatum, an organism described as a siphoneous 

 Alga, but ascertained to be identical with an animal — namely, 

 Zoobotryon pclhicidtim, Ehrenberg. He also exhibited two 

 specimens of a palm {Thrinax Morrisii, Wright), peculiar to 

 Anguilla in the Leeward Islands, and made some remarks as to 

 the results of the recent cryptogamic collections made by Mr. 

 W. R. Elliott for the West India Committee. — Mr. Holmes ex- 

 hibited and made some observations on an abnormal develop- 

 ment of the calyx in a primrose. — The President exhibited and 

 explained a collection of Lepidoptera containing several ex- 

 amples of mimicry between protected forms. — On behalf of Dr. 

 J. Muller, Mr. Thiselton Dyer communicated a paper entitled 

 "Lichenes Epiphylli Spruceani." — Mr. W. F. Kirby gave an 

 abstract of a paper on the family Saturnidce, with descriptions of 

 new species in the British Museum. — In the absence of the 

 author, Mr. W. Percy Sladen read a paper by the Rev. Hilderic 

 Friend, entitled "Observations on British Earthworms." — The 

 President announced that the anniversary meeting of the Society 

 would be held on May 24, at 3 p. m. 



Royal Microscopical Society, April 20. — The President, 

 Dr. R. Braithwaite, in the chair.— Mr. A. W. Bennett called 

 attention to some slides received from Prof. D. P. Penhallow, 

 of Montreal, who sent them to illustrate an improved method 

 of labelling. Instead of writing upon the usual paper label, he 

 writes directly upon the glass, and covers the writing afterwards 

 with a thin coating of Canada balsam, which makes it permanent. 

 — Prof. F. Jeffrey Bell said that, the Council having concluded 

 the negotiations with their landlords, the rooms of the Society 

 would now be open for the use of the Fellows every Wednesday 

 evening from 6 to 10 p.m., from November till June. This 

 order would take effect at once. — Mr. F. Chapman's paper 

 onthe Foraminifera of the Gault of Folkestone was read. — 

 Surgeon P. W. Bassett- Smith's paper on the deep-sea 

 deposits ot the Eastern Archipelago was read by Prof. Bell. 

 H. M.S. Peuguin, to which Surgeon Bassett-Smith was 

 attached, made a passage during the latter part of 1891 from 

 Port Darwin, North-west Australia, through the Arafora, Banda, 

 Celebes, Sulu, and China seas to Hong Kong. A continuous 

 and close line of soundings was taken through the whole 

 passage, the deepest water being 2880 fathoms in the Banda Sea. 

 In almost every instance specimens of the bottom were obtained. 

 They consisted mostly of "green muds," with a few "blue" 

 and "brown muds" in the deeper parts. The definition of 

 " green mud " is a very wide one ; broadly it may be divided 

 into that in which calcaieous organisms, chiefly Globigerina, pre- 

 dominate, and that in which the tests of Radiolarians have taken 

 their place ; this latter condition was almost always present in 

 "brown muds." The inorganic materials were either fine 

 quartz sand in the deeper and more distant positions, or, as the 

 coast was approached, argillaceous matter together with sponge 

 spicules and small shells. In places the material was typically 

 volcanic, as in the upper part of the Banda Sea, among the 

 Moluccas, and on the coast of Luzon. Only two specimens of 

 pure Globigerina ooze were obtained, both being in the Molucca 

 passage, one in 1885 fathoms and the other in 197 fathoms. 

 It would seem that in the deeper parts of the seas the bottoms 

 consist of Radiolarian muds, and the shallower parts of Globi- 

 gerina muds, the line being roughly drawn at 1500 fathoms. 

 In almost every case over 2000 fathoms the siliceous organisms 

 were undoubtedly most abundant.— A note was read from Dr. E. 

 Giltay on the use of the camera lucida in drawing Bacteria, 



