April 28, 1892] 



NATURE 



623 



SOCIETIES AND ACADEMIES. 

 London. 

 Entomological Society, April 13.— Mr. Henry John Elwes, 

 Vice-President, in the chair. — Mr. R. McLachlan, F.R.S., 

 exhibited specimens of a Caddis-fly remarkable for the abbre- 

 viated wings of the male, the female having fully developed 

 wings. He alluded to the Perlidcc as including species in which 

 the males were frequently semi-apterous. Dr. Sharp, F. R.S., 

 inquired if Mr. McLachlan was aware of any order of insects, 

 except the Neuroptera, in which the organs of flight were less 

 developed in the male than in the female. Mr. C. G Barrett 

 and Mr. H. J. Elwes cited instances amongst the Bomhycida in 

 which the wings of the male were inferior in size and develop- 

 ment to those of the female. — Dr. Sharp exhibited specimens of 

 both sexes of an apparently nondescript Phasmid insect allied to 

 Orobia, obtained by Mr. J. J. Lister in the Seychelles Islands, 

 together with /%_)////«;/; ^f/(7««j. He also exhibited specimens 

 of both sexes of an insect remarkable for its great general 

 resemblance to the PhasmidcE, though without resemblance, so 

 far as is known, to any particular species. In reference to the 

 Phyllium, Dr. Sharp called attention to the fact that the simi- 

 larity of appearance of parts of their organization to portions 

 of the vegetable kingdom was accompanied by a similarity, 

 amounting almost to identity, of minute structure. He said 

 that it had been stated that the colouring-matter is indistinguish- 

 able from chlorophyll, and that Mr. Lister had informed him 

 that when in want of food a specimen of the Phyllitim would 

 eat portions of the foliaceous expansions of its fellows, although 

 the Phasmida are phytophagous insects. The resemblance to 

 vegetable products reached its maximum of developLuent in the 

 egg ; and M. Henneguy had observed that when sections of 

 the external envelope of the egg of Phylliutn are placed under 

 the microscope no competent botanist would hesitate to pro- 

 nounce them to belong to the vegetable kingdom. — Mr. 

 Barrett exhibited, for Major J. N. Still, a s'^QZxme^xs oi Notodonta 

 bicolora, which had been captured in a wood near Exeter. 

 Major Still had stated that the captor of the specimen was 

 unaware of the great rarity of the species. Mr. Barrett also 

 exhibited, for Mr. Sydney Webb, some remarkable varieties 

 of Argynnis adippe and Coenonympha pamphilus ; also two 

 specimens of Apattira iris, and two of Limenitis sybilla in 

 which the white bands were entirely absent.— The Hon. Walter 

 Rothschild exhibited, and contributed preliminary notes on, 

 some hundreds of Lepidoptera, representative of a collection of 

 about 5000 specimens recently made by Mr. W. Doherty, in 

 the south-west of Celebes. Many of the species were new, and 

 others very rare. Mr. Elwes, Colonel Swinhoe, and Mr. 

 S. Stevens commented on the interesting nature of this collec- 

 tion.— Mr. E. B. Poulton, F. R.S., gave a lecture "On the 

 Denudation of the Scales in certain Species of Lepidoptera," 

 and illustrated it by a large number of photographs shown by 

 means of the oxy-hydrogen lantern. Mr. G. F. Hampson, 

 Mr. Elwes, and Mr. Poulton took part in the discussion which 

 ensued. 



Royal Meteorological Society, April 20.— Dr. C. Theo- 

 dore Williams, President, in the chair. — Reference was made to 

 the death of Dr. J. W. Tripe, who had held the office of Council 

 Secretary for the last twenty years, and a resolution of sympathy 

 with the family was passed by the meeting. — The following papers 

 were reai : — Anemometer comparisons, by Mr. W. H. Dines. 

 This w IS a report on a valuable series of experiments which 

 have been carried out at the request of the Council of the 

 Society, with the view of obtaining a direct comparison of the 

 various anemometers in common use, so that some opinion 

 might be formed as to which type of instrument is the most 

 suitable for general purposes. The Meteorological Council 

 have defrayed fhe cost of the work. The anemometers which 

 were compared were— (i) Kew pattern Robinson ; (2) self- 

 adjusting helicoid ; (3) air meter; (4) circular pressure 

 plate (one foot in diameter) ; and (5) a special modification of 

 tube anemometer. Most of these instruments are of the 

 author's own invention, as well as the apparatus for obtaining 

 automatic and simultaneous records from all the instruments 

 upon the same sheet of paper. It a|)pears that the factor of the 

 Kew pattern Robins )n is practically constant, and must lie 

 between 200 and 2-20. The helicoid anemometer is quite 

 independent of friction for all excepting light winds, and differ- 

 ent sizes read alike, but it is not so simple in construction as 

 the cup form. The air meter consists of a single screw 

 NO. I 1 74, VOL. 45] 



blade formed of thin aluminium, and made as nearly as possible 

 into the exact shape of a portion of a helicoid. A similar 

 instrument with a larger blade, and with the dial protected from 

 the weather, would probably form a useful and correct anemo- 

 meter. It would be light, and offer a very trifling resist- 

 ance to the wind. The oscillations of the pressure plate must 

 have been considerably damped by the action of the float- 

 ing weight, but as it was, they were sufficiently violent. It 

 seems probable that the remarkably high values sometimes 

 given by the Osier pressure plate may be due to the inertia of 

 the moving parts. The tube anemometer appears to possess 

 numerous advantages. The head is simple in construction, and 

 so strong that it is practically indestructible by the most violent 

 hurricane. The recording apparatus can be placed at any 

 reasonable distance from the head, and the connecting pipes 

 may go round several sharp corners without harm. Tlie power 

 is conveyed from the head without loss by friction, and hence 

 the instrument may be made sensitive to very low velocities 

 without impairing its ability to resist the most severe gale. — The 

 hurricane over the West Indies, August 18-27, 1891, by Mr, F. 

 Watts. The author has collected a number of observations on 

 this violent hurricane, which on August 18 swept from the 

 Atlantic into the Caribbean Sea, and moved in a nonh-noith- 

 westerly direction over San Domingo, and thence northward 

 and eastward. At Martinique the barometer, which at 5.30.p.m. 

 stood at 29-80 inches, fell to 28-38 inches at 8.15 p.m., during 

 the passing of the centre of the cyclone. 



Chemical Society, March 30. — Annual General Meeting.— 

 Prof. A. Crura Brown, F.R.S., President, in the chair.— The 

 President delivered an address, in the first part of which he 

 referred to the favourable position of the Society. In the 

 remainder of his address he dwelt chiefly on the work which is 

 being done on the border-lines of chemistry proper, referring 

 both to that by which an approach is gradually being made 

 towards understanding the che iiistry of Nature's organic 

 laboratory, and to the solution of chemical problems by the 

 application of mathematical and physical methods of inquiry. 

 A vote of thanks to the President was carried by acclamation, — 

 After the usual reports by the officers of the Society had been 

 presented, a ballot was taken for the election of officers and 

 Council for the ensuing year. The following were subsequently 

 declared elected :— President : A. Crum Brown, F.R.S, Vice- 

 Presidents who have filled the office of President : Sir F. Abel, 

 F.R.S. ; W. Crookes, F.R.S. ; E. Frankland, F.R.S; J. H. 

 Gilbert, F.R.S; J, H. Gladstone, F.R.S. ; A. W. Hofmann, 

 F.R.S.; H, Muller, F.R.S.; W. Odling, F.R.S.; W. H. 

 Perkin, F.R.S. ; Sir L. Playfair, F.R.S. ; Sir H. E, Roscoe, 

 F.R.S, ; W. J. Russell, F.R.S, ; A. W. Williamson, F.R.S. 

 Vice-Presidents: A. V. llarcourt, F.R.S.; W. N. Hartley, 

 F.R.S.; J, Pattinson; W. Ramsay, F.R.S.; W. A, Til- 

 den, F.R.S.; R. Warington, F.R.S. Secretaries: H. E, 

 Armstrong, F.R.S. ; J. M. Thomson. Foreign Secretary: 

 R, Meldola, F,R.S. Treasurer: T. E. Thorpe, F,R,S, 

 Ordinary members of Council : H, Bassett ; N. Collie : H, 

 Dixon, F.R.S. ; J. Ferguson ; R. J, Friswell ; J, Heron ; M. 

 M. P. Muir; F. J, M, Page; W. H. Perkin, Jun. F.R.S,; 

 S. U. Pickering; J. A, Voelcker ; W. P, Wynne. — Correction 

 of a note on a new acid from camphoric acid, by W, H, Perkin, 

 Jun. The author desires to express regret that he had over- 

 looked a previous paper by Damsky, in which an account is 

 given of the acid recently described by him as new. 



Mathematical Society, April 14.— Prof, Greenhill, F,R,S., 

 President, in the chair. — The following six foreign mathema- 

 ticians were elected Honorary Members of the Society, viz. 

 Messrs, Poincare, Hertz, Schwarz, Mittag-Leffler, Beltrami, 

 and Willard Gibbs. — The following short communications were 

 made: — Second note on a quaternary group of 51,840 linear 

 substitutions, by Dr. Morrice. — Note on the skew surfaces 

 applicable upon a given skew surface, by Prof, Cayley, F.R.S, 

 — Mr. A. B, Kempe, F.R.S., made an impromptu communica- 

 tion on regular graphs. — Mr, J. J. Walker, F,R.S,, Dr. M, J. 

 M. Hill, Lieut. -Colonel Cunningham, and the President joined 

 in the discussion on the above communications. 



Edinburgh. 



Royal Society, April 4.— Sir Arthur Mitchell, Vice- 

 President, in the chair. — Dr. Thomas Muir read a paper on a 

 problem of Sylvester's in elimination, and also a note on 

 Prof, Cayley's proof that a triangle and its reciprocal are in 



