NA TURE 



[May 13, 1Q09 



the exciting radiation was more penetrating than that 

 characteristic of the radiator. — Theory of the alternate- 

 current generator : Prof. Lyie. The author points out 

 that the theory of armature reaction as ordinarily dis- 

 cussed by electricians is unsatisfactory, as an important 

 effect due to the mutual induction between the current in 

 the field winding and the current in the armature circuit 

 is neglected. To simplify the problem, the case of a 

 simple ironless single-phase alternator is first discussed, 

 and then the effects of hysteresis and eddy currents. The 

 action of "dampers" in diminishing . the heat-losses in 

 the field circuit and the theory of the synchronous motor 

 are also discussed. 



Zoological Societv, April 27.— P. of E. A. Minchin, vice- 

 president, in the chair. — A review of the species of the 

 lepidopteran genus Lyc^enopsis, Feld. (Cyaniris auct. nee 

 Dalm.), on examination of the male ancillary appendages ; 

 Dr. T. A. Chapman. — (i) Some points in the structure 

 of Galidia clegans, and on the post-caval vein in 

 Carnivora; (2) the post-caval vein and its branches in 

 certain mammals : F. E. Beddard. — The comparative 

 osteology of the passerine bird Arachtwthera magna : Dr. 

 R. W. Shufeldt. 



Challenger Society. April 2S. — Prof. d'A W. Thompson 

 in the chair. — Photophores in Decapoda : S. W. Kemp. 

 While many decapods emit a luminous secretion from 

 various glands, true photophores are at present known 

 only in five species of the three genera Sergestes, 

 Acanthephyra, and Hoplophorus ; in all of them an in- 

 tensely blue pigment is associated with the organ ; in one 

 the pigment is situated in the corneal lens, in the others 

 in the (presumably) light-producing cup of cells which 

 lies immediately behind the lens, and the general body- 

 pigment is absent where they orrur. The organs increase 

 in number with age. and exhibit morphological stages. 

 They are placed much as in Euphausids. — A new method 

 of plotting currents from observations of drifters, used bv 

 the Scottish Fishery Board in the international studv of 

 the North Sea : Prof. Thompson. On a large chart divided 

 into squares of 1° lat. and \° long, all the observations 

 were recorded by arrows of true direction and proportionate 

 length : the " resultants " of these arrows, calculated for 

 each square, showed a uniform cyclonic current from Shet- 

 land down and across the North Sea to Norway, in con- 

 centric belts round the area of dead water which had been 

 shown to exist bv the observations of a previous vear. 

 Cambridge. 



Philosophical Society, March 8.— Prof. Sedgwick, presi- 

 dent, in the chair. — The nature of anthocyanin : Miss M. 

 Wheldale. The communication deals with the red- 

 purple-blue pigment " anthocyanin " occurring in plants. 

 Following up the suggestion made by various investigators 

 that there is some intimate connection between tannins and 

 anthocyanin, genera from various natural orders were 

 examined^ for tannin, and at the same time their pigments 

 were subjected to the action of various chemical reagents. 

 It was found that substances of the flavone series of 

 natural colouring matters are widely distributed in plants, 

 and from evidence based upon chemical tests and the results 

 obtained in genetics these fiavones appear to be essential 

 to the constitution of anthocyanin. — An experiment on 

 ionisation with 7 rays : L. Vegrard. The paper gives a 

 short account of some experiments made with the object 

 of finding whether the ionisation with y rays is strictly 

 an additive property. The additivitv is tried' for different 

 angles between the directions of the two rav bundles, and 

 in all cases the ionisation is found to be additive within a 

 fraction of i per cent. In the introduction the author 

 mentions that if the 7 rays consist of pulses with a con- 

 tinuous wave-front, some departure from additlvity under 

 certain conditions was to be expected. — The nature of the 

 ionisation produced in a gas by y rays : R. D. Kleeman. 

 It was found that when a volume of air is exposed to 

 y rays, and the ionisation in this volume by the secondary 

 kathode radiation from surrounding objects is eliminated 

 by a magnetic field, there still remains a considerable 

 amount of ionisation due to the direct action of the y rays 

 on the gas. Now, it has been shown by Eaby and Kaye 

 **iat the ionisation in an ionisation chamber due to the 



NO. 2063, VOL. 80] 



penetrating radiation from the gas is small in comparison 

 with the total ionisation. From a comparison of these 

 two results it follows that y rays produce, directly, 5 rays, 

 that is, kathode rays which have not sufficient velocity to 

 produce any further ions themselves. — Uniform oscillation : 

 Dr. Youngs. — The parametric representation of the co- 

 ordinates of points on a cubic surface in space of four 

 dimensions : H. W. Richmond. — The irreducible con- 

 comitants of two quadratics in n variables ; H. W. 

 Turnbull. 



M.^NCHESTER. 



Literary and Philosophical Society, Apiil 6. — Mr. F. 

 Jones, vice-president, in the chair. — Some colour demon- 

 strations of the dissociating action of water : R. L. 

 Taylor. When highly coloured solutions of ferric sulpho- 

 cyanide and ferric salicylate are diluted with water the 

 colour disappears. On the other hand, if a few drops only 

 of a solution of potassium permanganate are added to 

 half a litre of water a permanent coloration is produced. 

 The author pointed out that the peculiar behaviour of 

 these bodies was adequately accounted for by the " theory 

 of ionic dissociation," according to which the ferric sulpho- 

 cyanide and the ferric salicylate are dissociated into 

 colourless ions of iron and sulphocyanide, whereas the 

 potassium permanganate is dissociated into potassium and 

 coloured manganic ions. — Report on the recent Foramini- 

 fera from the coast of the island of Delos (Grecian Archi- 

 pelago) : H. Sidebottom. Some of the most interesting 

 forms described in the paper were Polytrema miniaceum, 

 Linnd-, sp., Trinicatn]ma variabilis, d'Orbigny, and a 

 decorated form of Rotnlin beccarrii, Linn^. — Permian foot- 

 prints : G. Hickling;. By the aid of numerous figures the 

 author showed the very close correspondence there was 

 between foot-prints found in the sandstones of Mansfield, 

 Notts, and Penrith, and those of the sandstones of Dum- 

 fries-shire and Elgin. The former rocks are undoubtedly 

 of Permian age, but the age of the Dumfries-shire and 

 Elgin sandstones is not definitely fixed owing to the few- 

 ness of the fossil remains found in them. The author 

 suggested that the identity of the types of foot-prints here 

 considered should be regarded as affording sufficient 

 evidence to fix the age of the rocks in which they occur 

 as Permian, and so settle a much controverted matter. 

 This conclusion, he added, was further strengthened by 

 the fact that not one of these forms could be matched by 

 those found in the Triassic rocks. 



Edinburgh. 

 Royal Society, May 3. — Prof. Ewart, F.R..S., vice-presi- 

 dent, in the chair. — Sirophanihus sarmcntosus, its pharma- 

 cological action and use as an arrow-poison : Sir Thomas 

 Fraser and Dr. A. P. Mackenzie. Slost of the material 

 had been collected by members of the Colonial Medical 

 Service in Nigeria, especially Dr. Dalziel and Dr. Dutton, 

 and a number of poisoned arrows had been supplied by 

 Sir Frederick Lugard. The main constituent in this arrow 

 poison was made from the seed of Sirophanihus 

 sarmeniosus, which resembled in its pharmacological 

 properties those of Sirophanihus hispidtis. To determine 

 its action an alcohol extract freed from substances soluble 

 in ether was used. A detailed account was given of its 

 action on the heart and skeletal muscles, both in small 

 and large doses. The effects on the heart are the most 

 important, small doses tending to produce a diastolic type 

 of change and large doses a systolic type. There seem to 

 be no direct effects on blood pressure or on respiration. — 

 The histological changes in the liver and kidney after 

 chloroform administered by different channels : Dr. G. 

 Herbert Clark. The chloroform was administered in three 

 ways : — (i) by inhalation ; (2) in olive oil by the stomach ; 

 (3) by injection into the subcutaneous tissues of the back. 

 By the first method the effect produced was very small. 

 By the second method the mortality was great, and the 

 organs underwent extensive changes and degeneration. 

 Similar effects were produced by the third method, although 

 the degree of degeneration was not so great. The changes 

 were described in detail, and illustrated by microscopic 

 slides. — The pathogenesis of Micrococcs meliiensis : Dr. 

 J. Eyre. The pathogenic effects produced by in- 

 oculation in various rodents and Carnivora were studied 



