November 26, 1914} 



NATURE 



345 



that wild ducks reared in Oregon and Washington 

 migrate into California, where they are ruthlessly shot 

 and sold. A Bill was introduced into the local legis- 

 lature last year with the object of remedying this state 

 of affairs, but was defeated as the result of a 

 plebiscite. The greater portion of the contents of the 

 first number of the new issue is devoted to arguments 

 in favour of amending the present anomalous condi- 

 tion of affairs. 



We have much pleasure in congratulating the Royal 

 Zoological and Acclimatisation Society of Victoria on 

 the attainment of its "jubilee." In the fiftieth report 

 of the council, for 1913, it is stated that the first 

 buildings in the then newly- formed gardens at Mel- 

 bourne were erected in June, 1862. The early efforts 

 of the society were entirely restricted to acclimatisa- 

 tion, and it was not until 1870 that "Zoological" was 

 added to its title, and that foreign animals were im- 

 ported solely for the purpose of public exhibition. 

 Judging from the photographs in the jubilee report, 

 the collection of such imported animals must now be 

 a fine one, but to an English eye the greatest attrac- 

 tion of the Melbourne Gardens must be the native 

 Australasian species, among which we may specially 

 refer to a group of tree-kangaroos or tree- wallabies, 

 photographed amid the branches of a tree, in the 

 report. 



According to the report of the general meeting held 

 on November 17, the Zoological Society is suffering 

 severely from the collateral effects of the war, the 

 number of visitors to the gardens during August, 

 September, and October being 307,826, or 124,154 lewer 

 than during the corresponding period of 1913. The 

 total number of visitors during the year has so far 

 been 1,011,526, and the take of gate-money 23,786/., 

 or a decrease in the number of visitors of 75,059 and 

 in the receipts of 2879Z., as compared with the first 

 ten months of last year. Nevertheless, the fact that 

 on October 25 the number of visitors who had passed 

 the turnstiles during the year reached a million is a 

 record which has been equalled only twice during the 

 last eighty-six years. Eighteen new fellows were 

 elected, and twent\-one candidates for the fellowship 

 or honorary membership and eight for the correspond- 

 ing-membership were proposed. The number of 

 fellows hitherto elected during the year is 263, or 

 three fewer than in the corresponding portion of 19 13, 

 this being, however, an increase of forty-seven above 

 the average at the corresponding date for the last 

 ten years. During August, September, and October 

 620 additions had been made to the menagerie — 444 

 by presentation, 51 by purchase, 58 on deposit, 29 by 

 exchange, and 38 born in the gardens. 



In the Ophthalmic Review for September, Dr. 

 Edridge-Green publishes a short account of his theory 

 of vision, and adduces the facts and arguments which 

 have led him to its adoption. According to this theory 

 the cones are the only terminal perceptive visual 

 organs, the function of the rods being confined to the 

 formation and distribution of visual purple. Vision 

 he supposes to take place by stimulation of the cones 

 through the photo-chemical decomposition of the liquid 

 in which they are bathed, this liquid being sensitised 

 NO. 2352, VOL. 94] 



by the visual purple. As against the argument that 

 the visual purple is absent from the macula lutea, the 

 region of most distinct vision, he adduces two observa- 

 tions by Devereux Marshall and himself on the eyes 

 of monkeys which had been kept in the dark for 

 forty-eight hours before being killed. He states that 

 in these circumstances the yellow spot was the reddest 

 part of the whole retina owing to the diffusion of 

 visual purple from the surrounding parts of the retina 

 between the cones. It is a pity that these observa- 

 tions have not yet been confirmed. Assuming their 

 correctness. Dr. Edridge-Green brings forward many 

 other considerations which tell in favour of his view. 

 An important point in his argument is the absence 

 of qualitative difference between central and pveri- 

 pheral vision, and he is supported by Tschermak, 

 Hering, Hess, and Garten in his assertion that the 

 difference between the vision of foveal and parafoveal 

 areas is merely quantitative. The difference between 

 the sensibility of the light and dark adapted eye he 

 shows to be analogous to the difference in the spectral 

 distribution of chemical effect with varying intensities 

 of illumination. Several subjective visual phenomena 

 are shown by him to agree with the theory. 



A USEFUL paper by Mr. B. C. Wallis entitled, "The 

 Distribution of Rainfall in the North-eastern United 

 States : its Causes and Results," is published in the 

 Scottish Geographical Magazine for November, based 

 upon observations contained in the annual report of 

 the United States Weather Bureau. The area em- 

 braces districts in which corn, cotton, and tobacco are 

 cultivated, and various maps and diagrams show by 

 means ot *' equipluves," or lines of equal average rain- 

 fall coefficients or percentages, the areas and dates 

 of the wettest and driest months, and consequently 

 the districts where such industries can best be carried 

 on. The diagrams show, among other things, (i) 

 that the maximum rainfall occurs between 130 and 

 140 per cent, of the normal, and that the minimum 

 occurs between 70 and 80 per cent, of the normal, 

 and (2) that in the north the rise in the rate of pre- 

 cipitation is faster than the fall, while in the Ohio 

 valley and to the south-east the opposite is the case. 

 The method is admittedly not new ; it is fully ex- 

 plained in the Quart. Journ. Roy. Met. Soc. for 

 October last (p. 311), and in an instructive note (p. 322) 

 Mr. C. Salter states that a very similar method (the 

 results of which were embodied in a paper to the 

 society on November 18) has been for some years 

 adopted by the British Rainfall Organisation. The 

 usual monthly rainfall averages are expressed as per- 

 centages of the annual value at each station ; in this 

 way some "exceedingly interesting facts" are dis- 

 closed, with many fewer stations than are necessary 

 when dealing with maps of actual monthly averages. 



An abstract of the results obtained by Mr. H. L. 

 Curtis, of the Bureau of Standards, during his tests 

 of the resistivities of nearly seventy insulating 

 materials, appears in the Journal of the Washington 

 Academy of Sciences for October 19. In all cases 

 contact with the material was made by means of 

 mercury electrodes, and the effects of surface leakage 

 were eliminated by the use of a guard ring. The 

 temperature of the specimen and the humidity of the 



