July i, 1922] 



NA TURE 



layer in the stem. A new shoot was also produced 

 in the axil of each of the cotyledons. — Sir Arthur 

 Shipley: buna infernalis. Linnanis was probably 

 I stung by a virulent insect which may have conveyed 

 to his system some pathogenic germs unknown at 

 that time. — T. A. Sprague : The identification of 

 Sison Amiui, Linn. Sison A mini is an umbelliferous 

 plant published by Linnteus in the first edition of the 

 I " Species Plantarum " in 1753. The type-specimens 

 ' in the Linnean Herbarium and the British Museum 

 I show that it is Cariini copticum, a medicinal plant 

 J which yields the Ajowan seeds and Ajowan oil, from 

 : which thymol is obtained. The history of the drug 

 I Ammi goes back to Dioscorides, who lived in the 

 ! first century of the Christian era ; he described it as 

 ' having a minute seed with the flavour of marjoram. 

 Various plants have been described as the Ammi, but in 

 the plates of Umbellifera? published by Rivinius at the 

 1 end of the seventeenth century, the officinal Ammi is 

 I Carum copticum. The geographical source of the drug 

 ! supports this conclusion. The best quality of Ammi 

 ' was imported from Alexandria, but was actually grown 

 in Arabia, where Carum copticum is still cultivated. It 

 hasnever been found ina wild state. — E. A. Newell Arber: 

 j Critical studies of coal-measure plant impressions. 

 The British Upper Carboniferous species of the genus 

 ! Lepidostrobus, Brongn., preserved as incrustations, 

 : and other impressions were discussed. — J . Burtt-Davy : 

 ] A revision of the South African species of Dianthus. 

 Thunberg's specimen of D. incurvus, Thunb., does not 

 : match any South African material at Kew or the 

 British Museum. Thunberg himself identifies it on 

 i the sheet with D. albens, Ait., but the specimen does 

 not agree with the type of D. albens in the British 

 i Museum. In the " Flora Capensis," Sonder recog- 

 nised nine species of Dianthus. Of these, seven only 

 are valid, and to them must be added four species not 

 recognised by Sonder. Six additional species and 

 three varieties are now described, bringing the total 

 I number up to seventeen species and three varieties. 



Royal Meteorological Society, June 21. — Dr. C. 



j Chree, president, in the chair. — J. E. Clark, H. B. 

 Adames, and I. D. Margary : Report on the phono- 

 logical observations for the year 1921. After mid- 

 December the mildness until late March was extreme, 

 which gave premature fruit blossom and its usual 

 concomitant of poor fruit crops, except apples. The 

 four early spring flowers were more than 18 days 

 earlier than the 30 years' mean ; April and May, 14 

 days, June, 10, and July, 6 days. Grain-cutting was 

 very early. The warm uprush along the Bristol 

 Channel, and up the Severn and Dee valleys to 

 include the Wirral Peninsula, was almost identical with 

 the isophenal trend and values for 1920. In the north- 

 east of Norfolk there was a recurrence of the cold 

 area so well marked in the years 1919 and 1920, 

 spreading southward from the North Sea, and curving 

 south-eastward by Norwich to include Bungay, and 

 also of the long tongue stretching from the Scottish 

 border southward to include Leicestershire and Rut- 

 land. The northerly bulge of warmth just north of the 



I Isle of Wight was again very definite. High ground 

 is, as before, indicated on the maps by relatively late 

 isophenal areas. Among exceptional effects were the 

 brief blooming period of the summer flowers and the 

 earliness of the autumn flowers, especially the Michael- 



!, mas daisies ; the dormant or destroyed seed-sowing 

 experiences ; the frequency of second blossom after 



1 the August rains, typically the horse-chestnut ; the 

 parly departure of the swallows ; the dearth of 

 tortoiseshell and allied butterflies, apparentlv from 

 lack of nettles. October had a week of unparalleled 



'heat, while November opened with severe frosts. 



NO. 2748, VOL. I lo] 



After a partial fall in late July, trees had retained 

 their foliage to an unusually late date, and those 

 frosts had the effect of making many of the leaves 

 brown and shrivelled as if from excess of heat. Planes 

 and elms kept their green leaves almost or quite until 

 December. — L. F. Richardson, A. Wagner, and R. 

 Dietzius : An observational test of the geostrophic 

 approximation in the stratosphere. Wind velocity, 

 at points not too near the earth's surface or the 

 equator, may be found with an accuracy of about 

 5 per cent, from the horizontal pressure gradient and 

 the rotation of the earth. A test of the error in- 

 volved in neglecting other considerations is obtained 

 by inserting the " geostrophic " velocities in the 

 equation for the accumulation of mass. Thus a 

 theoretical equality, valid in the stratosphere, be- 

 tween certain derivatives of wind and temperature is 

 obtained. From observations collected by Wagner 

 and Dietzius, the quantities which this theory makes 

 equal have a positive correlation of about four-tenths. 



Edinburgh. 

 Royal Society, May 8. — Prof. W. Peddie, vice- 

 president, in the chair. — Prof. E. T. Whittaker : The 

 quantum mechanism in the atom (see p. 23). — 

 A. R. Forsyth : Differential invariants and other 

 concomitants of quadratic differential forms in four 

 variables. The method is that of Lie's continuous 

 groups, and is thus entirely different from the Chris- 

 toff el method usually expounded. It provides new 

 results which the Christoffel method did not even 

 suggest. It can be applied to obtain Einstein's 

 critical form in the relativity theory of gravitation ; 

 on one hand, some of his conditions were covered 

 by others, and on the other hand his form satisfied 

 one equation more than the set he initially postulated. 

 — T. R. MacRobert : The asymptotic expansion of 

 the confluent hypergeometric function, and the 

 Fourier-Bessel expansion. 



Paris. 

 Academy of Sciences, June 6. — M. Emile Bertin 

 in the chair. — Ch. Boulanger and G. Urbain : The 

 composition and chemical characters of thortveitite 

 from Madagascar. Five complete analyses of this 

 mineral are given. The proportion of yttrium 

 earths does not exceed 0-5 per cent., while the 

 Norwegian mineral contains 4-18 per cent. Of this 

 group only yttrium, neoytterbium, and lutecium 

 could be detected. — MM. d'Arsonval, Bordas, and 

 Touplain : Study of the glacier waters of Argentiere 

 and Bossons. There are marked differences in the 

 electrical conductivity and chemical composition of 

 the waters from these two sources. — Carl Stormer : 

 Determination of the external magnetic field of the 

 sun by the structure of the solar corona and the 

 constants of the aurora borealis. — Louis Roy : 

 Electromagnetic actions in an isotropic system. — 

 G. Reboul : A new radiation and its application to 

 the study of the ultraviolet of Millikan and Lyman. 

 — A. Tian : Thermostats with multiple jackets. 

 The copper vessel containing the liquid to be main- 

 tained at a constant temperature, is surrounded with 

 felt and placed in one or more boxes, also of copper, 

 which are isolated in the same manner. The external 

 jacket is heated, and a uniform, steady temperature 

 can be thus maintained without stirring. The 

 advantages claimed for this system are that the 

 thermal oscillations due to the regulator are almost 

 entirely eliminated. The temperature of the inside 

 bath is practically independent of variations in the 

 room temperature, and stirring is not required. — 

 L6on and Eugene Bloch : Spark spectra in water. 



