NA TURE 



[July 15, 1922 



magnetic portions agree closely with the Baroti 

 i^roiip. — H. F, Collins : On some tr\ stallised sulphates 

 from the province of Huelva, Spain. Analyses arc- 

 given of pisanite, chalcantliitc. coquirnbite, copiapite, 

 voltaite, roemerite, etc., from various pyrites mines. 

 Experiments were made to determine the range of 

 miscibility of iron sulphate and copper sulphate in 

 mixed crystals of pisanite (R"S0 4 . . 7H 2 0) and chal- 

 canthite (R"S0 4 . 5H.O).— H. Hilton: the graphical 

 construction of the constants of a shear. A graphical 

 construction, based on the gnomonic projection, is 

 given for obtaining the two circular planes of a shear, 

 when the initial and final positions of two crystal- 

 poles or edges are known. — H. Hilton : A note on 

 crystallographic notation. A notation is suggested 

 for the 32 crystal-classes and the 230 groups of 

 movements, which is easy to write and print, and is 

 based on . the fundamental principles of structure- 

 theory.— A. F. Hallimond and E. G. Radley : On 

 glauconite from the Greensand near Lewes, Sussex ; 

 the constitution of glauconite. A boring through 325 

 feet of gault at Iford Manor yielded glauconite sand. 

 A discussion of the analysis of this material and of 

 some previously published analyses leads to the 

 formula R,0 . (4R 2 O a , RO) . 10S1O, . wH 2 0.— L. J. 

 Spencer ; Ninth list of new mineral names. 



Royal Irish Academy, June 12. — Prof. Sydney 

 Young, president, in the chair. — G. H. Carpenter and 

 Mi K. C. J. Phillips : The Collembola of Spitsbergen 

 and Bear Island. The collections made by the 

 Oxford University Expedition of 1921 include ten 

 species of Collembola, one of which — Folsomia 

 sexoculata — is an addition to the known fauna of 

 Spitsbergen, while another — an Isotoma closely 

 allied to the common I. viridis — taken on Bear Island 

 is new to science. Twenty species of .these insects 

 have now been recorded from Spitsbergen ; seven 

 of these have been found also on Bear Island, which 

 possesses, in addition, four species not vet detected 

 on Spitsbergen. Sixteen members of" this arctic 

 fauna are represented in Great Britain and Ireland, 

 while thirteen occur in Greenland and North America. 

 Such distributional facts suggest paths of migration 

 to the north of the Atlantic. 



Edinburgh. 

 Royal Society, June 19. — Prof. F. O. Bower, 

 president, in the chair. — J. Stephenson: On the 

 pharyngeal glands of the Microdrili (Oligochaeta). 

 The chromophil cells in the anterior segments of 

 the body of the Microdrili have, contrary to the usual 

 view, no direct communication with the alimentary 

 canal, and are not cells of the alimentary lining which 

 have retreated from the epithelial layer while still 

 retaining their connexion with it by means of a long 

 thin neck which acts as a ductule." They are meso- 

 blastic in origin ; in the enchytraeids (where they 

 form the septal glands) their secretion reaches the 

 pharynx by percolating along special strands of 

 tissue . in all other cases special channels are wanting 

 and the products of the cells simply mix with the 

 coelomic fluid ; their secretion is thus an internal 

 secretion. — \V. Peddie : On self light, fatigue, in- 

 hibition, and recurrent visual images. Formal 

 development of the trichromatic hypothesis is made 

 beyond the stage at which it was left at the time of 

 Helmholtz's death. Phenomena of contrast and 

 after images, steadily decaying or oscillatory, and 

 phenomena of fatigue and inhibition, are treated. 

 The trichromatic theory of colour vision is founded 

 securely on fact. — R. A. Fisher : On the dominance 

 ratio. The " dominance ratio " upon which the 

 relationship correlations depend, when inheritance 

 follows the Mendelian scheme, has a numerical value 



NO. 2750, VOL. I 10] 



for certain human measurements, very near to one- 

 third. This value presents a difficulty to the 

 Mendelian interpretation of the human relationship 

 correlations, in that it could occur only if the fre- 

 quency ratio of the several factors were unsym- 

 metrically distributed, in such a way that the domin- 

 ant phase was commonly more numerous than the 

 recessive phase. When, however, the effects of 

 selection are taken into account the distribution of 

 the frequency ratio may be calculated ; the dis- 

 tribution obtained is unsymmetrical in the manner 

 required, and the dominance ratio is exactly one- 

 third. The distribution produced by selection also 

 explains the occurrence among the non-recessives of 

 the harmful character sometimes brought out by 

 inbreeding. — A. P. Laurie : Chemical combination 

 and Sir Alfred Ewing's magnetic atom. Sir Alfred 

 Ewing's paper on hysteresis of iron has profound 

 significance for the chemist, for it shows that it is 

 possible to devise an atom of fixed and rotating 

 magnets free from polarity, and that on the approach 

 of another atom the rotating unit can be swung 

 into an unstable position and then fall into a new 

 stable position with evolution of heat. If we assume 

 the electrons to be moving in the tiny orbits but 

 arranged in space round a positive nucleus, the 

 results obtained by Sir Alfred Ewing can be applied 

 to chemical combination, ionisation, and catalytic 

 action. 



Official Publications Received. 



Royal Botanic Gardens, Kew. Bulletin of Miscellaneous Informa- 

 tion, 1921. Pp. 4 + 415 + 42. (London: H.M. Stationery Office.) 

 1. 



Department of the Interior: United States Geological Survey. 

 Water-Supply Paper 487 : The Arkansas River Flood of June 3-5, 

 11)21. By I: Follansbee and E. E. Jones. Pp. -It Water-Supply 

 Paper 17' Surface Water Supply "f the United States. 1918. Part 

 7: Lower MUsis-ippi Hiver Basin. Pp.38. (Washington: Govern- 

 ment Printing < Ifnce.) 



.Memoirs oi the Department of Agriculture in India. Botanical 

 Series, Vol, 11, No. 7: Correlation of Colour characters in Bice. 

 ByG. P. Hector. Pp. 153-183. (Calcutta: Thacker, Spink and Co. ; 

 London : Thaeker and Co.) 1.4 rupees; Is. Sr/. 



Smithsonian Miscellaneous Collections, Vol. 72. No. 15: Explora- 

 tions and Field- Work.. I tie -mi, it Ii-, man I, el it ill ion in 192 1. (Publica- 

 tion 2C.I-.9. 1 I'p. 12s (W.i-hm.'toi,: Smith-mian Institution.) 



Survej ot India. General Report, i"2n 21, from l-t Octobei L920 

 to 30th September 1921. Pp.-vi 18+8 maps, (Calcutta: Surveyor- 

 General's Office.) 2 rupees; 4s. 



Botanical Survey of South Africa. Memoir No. 4: A Guide to 

 irvey Work. Pp. 89. (Pretoria: Department of ftgri- 



iilt ii 



Southern Rhodesia. Geological Survey Bulletin No. 8: (1) The 



lieoloe\ mi the Diain Id.earinu Cra-vl-- ot tie* Somalmla Forest. 



by \ M Macgregor, with Notes bj te A. E. V. Zealley ; 121 on 



a Collection ot fossil Plants from Southern Rhodesia, by Dr. A. 0. 

 Seward and R. Ii. Holttum. Pp. 48 + 12 plates. (Salisbury: 

 Geological Survey I 



Board of Scientific Advice for India. Annual Report for tin- Year 

 1920-21. Pp. vii + 04. (Calcutta: Government Printing Office.) 

 12 annas. 



Imperial Department of Agriculture for the Wist Indies. Report 

 on the Agricultural Department, (ircnada, January-December 1921. 

 l'p. iv+15. (Barbados.) 6rf. 



Imperial Department of Agriculture for the West Indies. Report 

 mi tie \gricultural Department. Montserrat, 1929-21. Pp. iii + 33. 

 (Barbados.) (W. 



Diary of Societies. 



friday, july 14. 

 International Neo-Malthtjsian and Bikth Control Conference 



(at Kingswaj Hall, Kingsway, W.C.2), at 10.— Dr. C. K. Millard: 



Birth Control and tin Medical Profession.— Dr. A. Nystrdm : The 



Neee*Mt\ lor alioli-hite: fan. against Preventive Measures.— 



Dr. II Rohledei : Neo-Malthu ianism from the Medical standpoint. 



— N Han.-- Sterilisati the Unfit. Dr. D. R. Hooker : Effect 



of X-ra\s upon Reproduction in the Rat. 

 International Conference of Settlements (at Toynbee Hall. 28 



Commercial street, E.l), at 10 and 2.15. V Greenw 1. Miss E. M. 



McDowell, F. .1. .Marquis, J. J. Mallon, and others : Settlements ami 



Industry. 



SATURDAY, Jn,v 15. 

 International Conference of Settlements (at Toynbee Hall, 28 



Commercial Street. 10.1), at 10.— H. It. Aldridge, T. Adams, ('apt. 



Reiss, Rev. D. MacFadyn, and ot). s : The Relation of Settlement? 



to Health and Housing Reform. 



WEDNESDAY, JULY 19. 

 Fellowship or Mk.pkinf. (at I Wimpole street, w.l), at 5. — V. 

 Bonney : Myomectomy as opposed to Hysterectomy. 





