March 31, 19 10] 



NATURE 



147 



accounted for as perfectly as the present state of the 

 nieasurements permits. — G. C. Simpson : Earth-air 

 electric currents. The paper describes a method for record- 

 ing automatically the electrical current which passes from 

 the earth into the air during periods of fine weather. A 

 large plate (17 metres^) was placed in the open as near 

 to the ground as was consistent with efficient insulation ; 

 this was then connected to an insulated vessel, from which 

 water issued through an orifice surrounded by an earth- 

 connected cylinder. The water as it dropped from the in- 

 sulated vessel carried away, by the well-known " collector " 

 action, all the charge which the exposed plate received, 

 and the latter remained at zero potential. The charged 

 water drops were collected in a vessel connected to a self- 

 registering electrometer, which was earth-connected for an 

 instant at the end of every two minutes. The paper 

 describes the sources of error and the method of determin- 

 ing the value of the earth-air current and of the con- 

 ductivity of the air from the records of the electrometer. — 

 Dr. B. D. Steele : An automatic Toepler pump designed 

 to collect the gas from the apparatus being exhausted. 



Zooloerical Society, March 15.— Mr. E.T.Newton. F.R S.. 

 in the chair. — T. Goodey : A contribution to the skeletal 

 anatomy of the fish Chlamydoselachus anguineus. Gar. 

 The author dealt with the anatomy of the axial and 

 appendicular skeleton, paying particular attention to the 

 structure of the notochord. He stated that the notochord 

 in this fish had generally been regarded as unconstricted 

 except at the extreme anterior extremity, but that he had 

 ascertained the presence of well-developed, calcified cyclo- 

 spondylic centra at the anterior end of the column, and 

 of calcified cyclospondylic centra of two sizes in the main 

 caudal region. — W. R. Ogri'vie-Grant : Additional notes 

 on the birds of Hainan. The notes were based on a 

 small collection of Hainan birds recently forwarded to the 

 Zoological Society by Mr. Robert Douglas, of Shanghai, 

 and, at the suggestion of Dr. Chalmers Mitchell, F.R.S., 

 presented to the Natural History Museum. The collec- 

 tion contained several species of great interest, and two 

 were described as new, nameh', Tephrodornis hainanus 

 and Pitta douglasi. Among the rarities, attention was 

 directed to the remarkable magpie (Temnurus niger), with 

 its curious truncate tail-feathers, the beautiful green jay 

 (Cissa katsumatae), recently described by the Hon. Walter - 

 Rothschild, and a bu'bul (Pycnonotus sinensis), not 

 hitherto recorded from the island. — Dr. Einar LSnnberg: : 

 The variation of the sea-elephants. 



Royal Meteorological Society, March 16. — Mr. H. 

 Mellish, president, in the chair. — Captain H. G. Lyon* : 

 Climatic influences in Egypt and the Sudan. From early 

 times the ancient Greeks recognised the marked difference 

 between the climate of the Mediterranean and that of 

 -Africa,^ and Aristotle indicated correctly the rains of 

 Ethiopia as the cause of the annual flood of the Nile. 

 Travellers have supplemented our knowledge from time to 

 time, but only within the last ten years has a network of 

 meteorological stations given precision to our views and 

 furnished a basis for further investigations. The com- 

 paratively low relief of the country, which lies as a vast 

 land area in low latitudes, combined with the effect of 

 the north-easterly trade winds which sweep over it, pro- 

 duce the hot and dry conditions which are so characteristic 

 of north-eastern Africa. Modified somewhat in the north 

 by the warm waters of the Mediterranean, and in the south 

 by the rains of the monsoon in summer, the highest 

 temperatures and most arid conditions are reached between 

 Wadi Haifa and Dongola, where northerly winds, clear 

 skies, and a great range of temperature prevail throughout 

 the year. The important rains are those falling in Uganda, 

 the southern^ plains of the Sudan, and on the tableland of 

 Abyssinia, since they not only provide the whole supply 

 of the Nile and its tributaries, but largely control their 

 regimen. Fed by the south-easterly air currents blowing 

 in from the Indian Ocean, these monsoon rains supply the 

 equatorial lakes and the tributaries of the Nile; but it is 

 the Abyssinian tableland, with its heavy summer rainfall, 

 which is most effective, since it furnishes the whole of 

 the Nile flood and enables the Nile to maintain itself 

 NO. 2109, VOL. 83] 



through 1500 miles of desert. As the sole source of the 

 flood, the variation of these rains directly determines the 

 abundance or deficiency of Egjpt's supply, so that this 

 climatic problem is of immense importance. Hardly less 

 important in these days of intensive cultivation of cotton 

 is the study of the winter storms which occasionally break 

 in the Sudan and Abyssinia, raising the level of the rivers 

 and increcising the supply of the Nile appreciably at a time 

 when the normal supply is inadequate. The climate of 

 the region not only influences the water supply, but the 

 great range of temperature rapidly disintegrates the rocks, 

 and the wind removes the finer portion of the material. 

 In this way the deserts are being constantly modified, and 

 vast ranges of sand dunes are piled up. The distribution 

 of vegetation is very markedly influenced both by the 

 moisture and by the physical character of the country'. 



Linnean Society, March 17. — Dr. D. H. Scott, F.R.S., 

 president, in the chair. — E. P. Stebbing : The life- 

 history of Chermes himalayensis on the spruce {Picea 

 Morinda) and silver fir (Abies Webbiana) of the N.VV. 

 Himalaya. The life-histories of the European species of 

 Chermes, C. abietis and C. viridis, have been studied by 

 Blochmann and L. Dreyfus in Germany, Cholodkovsky in 

 Russia, and more recently by E. R. Burdon, of Cambridge. 

 It is now well known that C. viridis has alternating series 

 of generations upon the spruce and larch. The discovery 

 that a species of Chermes formed galls on the spruce in 

 the Himalaya was first reported by A. Smj-thies, of the 

 Indian Foreign Service, in 1892. These were considered 

 by the late Mr. Buckton to be Chermes abietis. Investiga- 

 tions commenced by the author in May, 190 1, and carried 

 on intermittently up to July, 1909, have led to the discovery 

 that this Chermes, although an undescribed species, has a 

 life-history somewhat similar to the European species of 

 the genus, having series of agamic generations alternating 

 betw-een the spruce and silver fir (which grow together in 

 mixture in the western Himalaya), with a sexual genera- 

 tion occurring but once a j'ear, in the autumn, on the 

 spruce. The paper shows that the Himalayan insect 

 passes through similar generations to its European con- 

 geners, to which the names Fundatrices, Alatae, Colonici, 

 Sexuparae, and Sexuales have already been given by Euro- 

 pean investigators. The periods at which these generations 

 are to be found upon the trees in the Himalaya differ con- 

 siderably, however, from the European ones, and are 

 apparently chiefly governed by the appearance of the mon- 

 soon early in July in this region. — R. S. Baenall : A 

 contribution towards our knowledge of the neotropical 

 Thysanoptera. 



Institution of Mining and Metallurgy, March 17. — 

 Mr. Edgar Taylor, president, in tHe chair. — ^W. A. 

 MacLeod : The surface condenser in mining power 

 plant. The author conducted a number of tests on the 

 winding engines of a mine with which he was connected, 

 the results of which were embodied in this paper, together 

 with a vast amount of other information concerning the 

 relative consumptions and efficiencies of condensing and 

 non-condensing engines. He found that the employment 

 of condensers was distinctly beneficial in both respects, 

 even under the intermittent conditions attaching to most 

 mining power plants, and the results of his investigations 

 have enabled him to determine with some exactness the 

 leading features to be emphasised in the laying down of 

 a condensing plant suitable for work of a more or less 

 intermittent nature, as in the case of winding engines. 



Cambridge. 



Philosophical Society, February 21. — Prof. Seward, vice- 

 president, in the chair. — Prof. Punnett : Mimicry in 

 Ceylon Rhopalocera, with some notes on the enemies of 

 butterflies. — A. R. Browwn : The Andaman Islands. Some 

 of the features of the physical anthropology and the social 

 life of the aborigines of the Andaman Islands were briefly 

 described. The extremely primitive characteristics of the 

 Andamanese are to be attributed to their long isolation from 

 all other races and peoples, and the stability* of population. 

 — ^T. G. Edwwarfils : The procession and pupation of the 



