178 



NATURE 



[October 14, 19 15 



environment as a whole the greater becomes the pro- 

 portion of asymmetrical forms. The two main factors 

 in producing- asymmetry are bathymetrical and 

 thermal. This feature is least developed at the opti- 

 mum temperature for crinoid .life, and most developed 

 in temperatures which are phylogenetically too warm 

 or too cold. Excessive cold appears to be the deter- 

 mining factor in the asymmetry of the genus Pro- 

 machocrinus; while the opposite condition, excessive 

 warmth, similarly affects the family Comasteridae. In- 

 ternal unfavourable conditions, the author insists, have 

 also to be taken into account, such, for example, as 

 are induced by incipient phylogenetical degeneration 

 through type-senescence, as in the Plicatocrinidae, 

 which, in recent seas, represent the almost exclusively 

 Palaeozoic Inadunata. 



A FURTHER instalment of Mr. J. F. Duthie's "Flora 

 of the Upper Gangetic Plain" has now been pub- 

 lished. The present section, which forms part i. of 

 vol. iii., deals with the families Nyctaginaceas to 

 Ceratophyllaceae, and occupies i68 pages. The Euphor- 

 biaceae and Urticaceae are among the most important 

 of the families included, the former with twenty-one 

 genera and the latter with seventeen. The genus 

 Ficus, which has some 600 species, is represented in 

 the Upper Gangetic plain by eighteen species, among 

 which are such well-known trees as Ficus bengalensis 

 and F. religiosa. 



Monthly Weather Reviews are published with great 

 regularity by the Government of India, and the issue 

 for March, 1915, shows considerable activity on the 

 part of the meteorological department. The review, 

 which is drawn up under the superintendence of 

 Dr. G. C. Simpson, is based on observations 

 taken daily at 8 hrs. at 215 stations, and on additional 

 observations taken at 10 hrs. and 16 hrs. at 14 

 stations. For the summary of rainfall, observations 

 are used from about 2,300 stations. March was re- 

 markably wet over by far the greater part of the 

 Indian area, and with these conditions the air was 

 damper and the sky more cloudy than usual in most 

 parts of the country. The departures from normal 

 temperature were generally feebly marked, whilst the 

 barometric pressure in the plains was in excess of the 

 normal. Observations are given of solar, magnetic, 

 and seismic disturbances. Much detailed information 

 can be obtained from the tabular results and from the 

 illustrations contained in the review. 



Rainfall values for August, 1915, are given in 

 Symons's Meteorological Magazine for September, 

 and the results show very varied conditions for the 

 month. Last August is so commonly quoted as being 

 wet that it is somewhat surprising to find that the 

 percentage of the average rainfall was 72 for England 

 and Wales, 68 for Scotland, 83 for Ireland, and 75 

 for the British Isles as a whole. The London rainfall 

 was 95 per cent, of the average, from the observq^ 

 tions at Camden Square, but it may be remarked that 

 the rainfall was much heavier at South Kensington, 

 the recording station of the Meteorologcal Office, 

 where the fall was about 50 per cent, above the 

 normal. The values given for the several stations in 

 NO. 2398, VOL. 96] 



different parts of the British Isles show very varylni; 

 results. The greatest excess on the normal occurred 

 at Shoeburyness, where the fall was 166 per cent, of 

 the average, and this is at a station which is notably 

 one of the driest in the whole kingdom. Scathwaite, 

 which is normally the wettest portion of the kingdom, 

 had only 37 per cent, of the average, which is as great 

 a deficiency for August as any part of the countr\ . 

 The map giving the rainfall for the Thames Valle\ 

 shows that the rains were extremely irregular and 

 patchy, particularly in the neighbourhood of London. 



A NOTE on the divide produced by a plate in a 

 moving liquid is contributed by Mr. Tsuruichi Hayashi 

 to the Tohoku Mathematical Journal, viii., i. The 

 author arrives at the conclusion that " the divide is 

 the locus of point (sic) from which two shortest 

 equal normals can be drawn to the periphery of the 

 plate immersed." But this result is based on an 

 assumption for which justification is sought in quota- 

 tions from Duchemin's results, taken from De Villa- 

 mil's recent book on "Motion of Liquids," with ex- 

 planatory additions in square brackets. From these 

 extracts the Japanese writer bases his conclusions 

 on the assumption that the lines of flow along the 

 face of the plate are straight lines normal to the 

 boundary. Unfortunately, however, this assumption 

 appears to be based on a distorted quotation of 

 Duchemin's actual statements, and the reference to 

 "curved" diagonals in the case of a rectangular 

 plate, which is attributed to Duchemin, would appear 

 to " unjustify " (if such a word may be made) the 

 interpretations which have led to the present writer's 

 conclusions. It is easy to construct cases where the 

 result would evidently not hold good, in particular in 

 the case of figures with re-entrant angles, or again, 

 figures composed of two or more separate areas. 



An important paper, which marks a real advance 

 in the chemistry of the sulphites, has been contributed 

 to the September issue of the Journal of the Chemical 

 Society by Mr. C. S. Garrett from the University of 

 Liverpool. It is shown that no power of selective 

 absorption of light is possessed by the neutral 

 sulphites, such as Na-jSOa, or by the two types of 

 alkyl sulphites, such as C2H,.6.SO.O.C2H5 and 

 CjH-.SOo.O.C.H^. Sulphurous acid in aqueous solu- 

 tions, on the other hand, gives a very well-marked 

 maximum of absorption at wave-length 2760. The 

 important discovery is now announced that the acid 

 sulphites, such as NaHSO,, and the metabisulphites, 

 such as Na^S^O., show no selective absorption in 

 freshly prepared aqueous solutions, but develop this 

 property after keeping for some weeks, especially if 

 exposed to light. It is suggested that this alteration 

 of properties is due to the chemical changes repre- 

 sented by the equations — 



2NaHSO,— Na.SO, + H,SO, 

 H^O + Na,S,0;— Na.SO^ + H:S0;„ 



whereby the non-absorbent compounds on the L.H. 

 of the equation are converted into a non-absorbent 

 sulphite and an absorbent form of sulphurous acid. 

 Incidentally, it follows that this absorbent compound 

 must have a different structure from that of all its 



