58 



NATURE 



[March 20, 19 19 



have no meaning for us. The existence of other 

 selves cannot be inferred, as is usually supposed, 

 from the analogy which their behaviour presents to 

 our own, because (i) no priority attaches to the 

 awareness of our own selfhood ; (2) the alleged infer- 

 ence would have to be made for the first time at an 

 impossibly early age ; (3) the behaviour of others 

 presents, from the point of view of the percipient, no 

 analogy to his own ; and (4.) if other selves were 

 merely inferred entities, human affections and rela- 

 tionships could not be what they are. It is con- 

 sistent with any theory of the ultimate nature of mind 

 to maintain that the presence of other selves and the 

 affective aspect of them can be directly apprehended. 



Mathematical Society, March 13. — Mr. J. E. Camp- 

 bell, president, in the chair. — J. Hammond : The solu- 

 tion of the quintic.^ — L. J. Mordell : A simple algebraic 

 summation of Gauss's sums. — Major P. A. MacMahon : 

 Divisors of numbers and their continuations in the 

 theory of- partitions. — S. Ramanujan : (i) Congruence 

 properties of partitions. (2) Algebraic relations between 

 certain infinite products. 



Linnean Society, March 20.- — Sir David Prain, presi- 

 dent, in the chair. — Dr. Harold Wager : The colour- 

 sense of wasps. The experiments described in this 

 paper were made by observing the number of wasps 

 flying towards, and settling upon, pieces of sugar 

 placed upon sheets of coloured paper arranged in 

 various wa3?s. The results show that in seeking their 

 food wasps {Vcs^a vtdgaris) are guided by their social 

 instinct, their remembrance of locality, and their 

 power to distinguish conspicuous colours or colour- 

 contrasts. They are probably also guided by smell, 

 but no experiments were made to test this. Leaving 

 out of account the probability that smell plays an 

 important part in their activities, the experiments 

 indicate jthat the governing principles which dominate 

 wasps in their search for food are, first, the attraction 

 exerted by the presence of other wasps ; secondly, the 

 tendency always to return to the same place; and, 

 thirdly, the attraction due to conspicuous colours and 

 colour-contrasts. 



Cambridge. 



Philosophical Society, February 17.— Mr. C. T. R. 

 Wilson, president, in the chair.- — Dr. Doncaster : Note 

 on an experiment dealing with mutation in bacteria. 

 It was noticed that the recorded ratio of occurrence in 

 cases of meningitis of the four agglutination-types of 

 Meningococcus corresponded very closely with the ratio 

 of occurrence of the four iso-agglutinin groups of blood 

 in a normal human population. It seemed possible, 

 therefore, that by growing Meningococcus of one type 

 in media containing human blood of different groups, 

 mutation to other types might be induced. Experi- 

 ment showed that considerable differences in type of 

 agglutination resulted, but it was concluded that this 

 was caused by the sorting out of races of different 

 agglutinability from a mass culture rather than by 

 true mutation. — Dr. Shearer : Electrical conductivity 

 of bacterial emulsions. — Miss M. D. Haviland : The 

 bionomics of Aphis grossulariae, Kalt, and A. viburni, 

 Shrank. A. grossulariae, a pest of currant-bushes, 

 appears to be identical with A. grossulariae found on 

 the guelder rose. Experiments to see how far the 

 descendants of the original migrants can be success- 

 fullv transferred from the currant to the guelder rose, 

 and vice versa, show that while the guelder-rose form 

 can with some difficulty be cultivated on the currant, 

 the currant form cannot be reared on the guelder rose. 

 — J. E. Purvis : (i) The conversion of sawdust into 

 sugar. (2) Bracken as a source of potash. — S. 

 Chapman : Terrestrial magnetic variations and their 

 connection with solar emissions which are absorbed in 



NO. 2.S77. VOL. 103] 



the earth's outer atmosphere.— W. J. Harrison : The 

 distribution of electric force between two electrodes, 

 one of which is covered with radio-active matter. It 

 would appear from experimental results that the rate 

 of ionisation per unit time due to an a particle is con- 

 stant at all points of the path of the particle within 

 the range of its ionising activity. It follows that, at 

 a distance x from a large electrode covered with radio- 

 active matter, the rate of ionisation is g„log(R/rc), 

 where R is the range of the particles. The differential 

 equations involved are integrable in the case of the 

 saturation current, and typical numerical solutions 

 have been calculated 



Dublin. 

 Royal Dublin Society, Februarv 25.^Prof. J. Joly 

 in the chair.— W. B. Wright : ' An analysis of the 

 Palaeozoic floor of north-eastern Ireland, with pre- 

 dictions as to concealed coalfields. The considerations 

 which led up to the present search for coal beneath 

 the basin of Lough Neagh are elaborated and sup- 

 ported by further evidence. These considerations w^re 

 originally set forth in 1917 in a memorandum from 

 the Geological Survey of Ireland to the Department 

 for the Development of Mineral Resources, Ministry 

 of Munitions. They are now extended to the predic- 

 tion of coal basins in other parts of the concealed 

 area. Thesfe basins are located at the intersection of 

 certain well-marked north and south synclinal troughs 

 with the continuation of the central trough-vallev of 

 Scotland, and a distinct doubly synclinal trough with 

 Caledonian trend lying further north. 



Manchester. 

 Literary and Philosophical Society, March 4. — Mr. W. 

 Thomson, president, in the chair. — F. H. Carr : The 

 post-graduate training of the works chemist. There 

 was scope for institutions devoted primarily to the 

 post-graduate training of chemical students who in- 

 tended to specialise in the applied aspects of their 

 science. In such institutions instruction would be 

 given, not only on a wide variety of technical pro- 

 cesses for the manufacture of chemicals, and in opera- 

 tions in each technical department, from the drawing 

 office and the" power house to the special chemical 

 plants, but also in the whole question of economic and 

 statistical control of works processes. The chemicals 

 produced should cover an extremely wide range, and 

 be such as might be required in relatively small 

 quantities such as existing manufacturing firms would 

 not find it worth while to produce. In, this way the 

 institutions in question might, in course of time, 

 accumulate stocks of chemicals comparable in variety 

 with those in the possession of certain German firms 

 on the resources of which research chemists in all 

 parts of the world have had to rely. 



Sydney. 

 Linnean Society of New South Wales, November 27, 

 1918. — Prof. H. G. Chapman, president, in the 

 chair.— Dr. R. J. Tillyard : Studies in Australian 

 Neuroptera. No. 6 : The family Psychopsidae, with 

 descriptions of new genera and species. The 

 paper begins with a study of the wing-venation 

 of Psychopsis elegans, Guerin, which is com- 

 pared with the t)recedent tracheation of the pupal 

 wing. From this it is shown that the family is 

 characterised by certain specialisations not found in 

 other families, and that the cross-venation, which 

 consists only of a variable number of gradate series. 

 Is to be considered as a comparatively late addition to 

 the original Prohemeroblld-like venational scheme. 

 The character of the cross-venation is shown to be 

 essentially variable, and the classification of the family 



