46 



NATURE 



[November 12, 1891 



theory of symmetric functions. The author has extended the 

 subject of these memoirs in a paper with the title " Memoir on 

 symmetric functions of the roots of systems of equations " in 

 the Philosophical Transactions, A. (1890). — The next paper, by 

 C. P. Steinmetz, was read before the New York Mathematical 

 Society, and is entitled " Multivalent and univalent involutory 

 correspondences in a plane determined by a net of curves of wth 

 order." — The following note, also read before the same Society, 

 is on the algebraic proof of a certain series. It supplies a 

 " temporary lack," which was regretted by- the author, E. 

 McClintock, in a memoir which will be found in vol. ii. p. 108. 

 The same writer furnishes another addition to the memoir just 

 referred to (vol. ii.), on independent definitions of the func- 

 tions log X and ^. — H. B, Newson writes on a pair of curves 

 of the fourth degree, and their application in the theory of 

 quadrics ; and H. P. Manning finishes this instalment with a 

 note on linear transformation, which was suggested by a method 

 employed by Prof. Cayley, F.R.S., in vol. v. of the Amer. 

 Journal. 



The articles in the numbers of the yournal of Botany for 

 October and November are mostly of interest to specialists in 

 local floras. Mr. A. Fryer describes and figures a new Eng- 

 lish Potaniogeton (or, rather, hybrid). Mr. T. H. Buffham 

 describes and figures the hitherto unknown plurilocular sporanges 

 in two sea- weeds, Asferococcus buUosus and Myriotrichia clavce- 

 forniis. Mr. F. N. Williams contributes a synopsis of the 

 l)rimary characters in the species of Rheum. 



The last number received of the Botanical Magazine published 

 at Tokyo, Japan (for June), contains an interesting article, 

 illustrated, on a new Japanese Prasiola, P. japonica, by Dr. R. 

 Yatabe, which, the author states, is collected in large quantities 

 in the districts where it grows, and is sold as an article of food 

 under different names in different localities. It is eaten either 

 slightly broiled or with vinegar, the mode of preparation being 

 very similar to that of the ordinary purple and green lavers. 

 Other articles in the same number are on the reproduction of 

 Laminaria japonica ; on a recent problem in vegetable physio- 

 logy (apparently the greatly discussed question of the direct 

 absorption of nitrogen from the air by plants) ; and on the 

 colours and scents of flowers ; but as all these are unfortunately 

 in Japanese, they are inaccessible to the English reader. 



The number of the Nuovo Giornale Botanico Italiano for 

 October is chiefly occupied with the^ Proceedings of the Italian 

 Botanical Society. The attention of Italian botanists is still 

 directed to the interesting phenomena connected with the pol- 

 lination of the Aroidese : Signor Caleri has a paper on the 

 flowering of Arum Dioscoridis, and Prof. Arcangeli one on the 

 fertilizers of Helicodiceros muscivorus. He is unable to discover 

 any evidence that the latter plant is really carnivorous. — Signor 

 Martelli discusses a vine-disease which has lately appeared in 

 the neighbourhood of Florence, and which he identifies with 

 the " black rot " of the American grape, caused by a Pyreno- 

 mycetous fungus, Physalospora Bidwelli. 



SOCIETIES AND ACADEMIES. 

 London. 

 • EntomologicalSociety, October 7. —Dr. D. Sharp, F.R.S., 

 Vice-President, in the chair. — The Chairman referred to 

 the death, on September 14 last, of Mr. E. W. Janson, who 

 had been a member of the Society since 1843, ^"^ who had 

 f .rmerly filled the offices of secretary and librarian respectively. 

 — The Rev. Dr. Walker exhibited a long series of several 

 species of Erebia, and of Argynnis pales, which he had recently 

 captured near Roldal, in Norway. — Mr. W. L. Distant ex- 

 hibited specimens of Danais chrysippus, with its two varietal 

 forms, alcippus, Cram., anddorippus, Klug., all which he found 

 together in the Pretoria district of the Transvaal. Mr. Jenner 

 Weir and Colonel Swinhoe took part in the discussion which 

 ensued as to these forms and their distribution. — The Rev. W. 

 Y. Johnson sent for exhibition specimens of Velia currens from 

 stagnant water near Armagh ; also a specimen of Nabis limbatus, 

 killed whilst holding on to its prey, a very hard species of 

 Ichneumon. Mr. Saunders thought that, from the nature of the 

 Ichneumon, the only chance the Nabis had of reaching its in- 

 ternal juices would be through the anal opening, as recorded by 

 Mr. E. A. l^yiXXeT in a. s,imWz.rc3iS,&,\nthQ Entomologist's Monthly 

 Magazine, October 1891. — Mr. F. P. Pascoe exhibited two British 



NO. II 50, VOL. 45] 



species of Diptera, unnamed. He said they had been submitted 

 to Mr. R. H. Meade, but were unknown to him, and are prob- 

 ably new to the British list. — Mr. R. Adkin exhibited tw 1 

 specimens of a supposed new species of Tortrix ( Tortrix donc- 

 lana. Carpenter), bred from larvae found on pine-trees at Tuam. 

 Mr. C. G. Barrett said he examined the specimens with great 

 care, but he did not consider that they belonged to a new 

 species. He was unable to distinguish them from Tortrix 

 viburnana. — M. A. Wailly exhibited preserved larvae, in 

 various stages, of atheroma regalis, which he had bred from 

 ova received from Iowa, United States. He said that the 

 natives called this larva the Hickory Horned Devil, and that the 

 specimens exhibited were the first that had been bred in this 

 country. M. Wailly further exhibited three female specimens 

 of Antheraa yama-mai bred from cocoons received from Japan ; 

 also a nest of cocoons of Bombyx radama, received from the 

 west coast of Madagascar. Prof. J. B. Smith, of the United States, 

 and Colonel Swinhoe took part in a discussion on the habits 

 of the larvae of Citheronia regalis, and as to the period at which 

 they dropped their spines prior to pupating.— Dr. Sharp ex- 

 hibited several specimens of a weevil, Ectopsis ferrugalis, the 

 ends of the elytra of which bore a close resemblance to the section 

 of a twig cut with a sharp knife. He said he had received the 

 specimens from Mr. G. V. Hudson, of Wellington, New Zealand, 

 who stated that they were found resting in large numbers on 

 dead trunks and branches of Panax arborea in the forests. — Mr. 

 G. C. Champion stated that the species of Forfictilida:, captured 

 by Mr. J. J. Walker, R.N., in Tasn)ania, and exhibited by 

 himself at the meeting of the Society in April last, was, he 

 believed, referable to Anisolabis tasmanica, Bormans, described 

 in the Coviptes rendus of the Ent. Soc. Belgique, 1880. — The 

 Rev. A. E. Eaton made some remarks on the synonymy of the 

 PsychodidcB, and stated that, since August 1890, he had identi- 

 fied all of the British species in Mr. Verrall's list, except 

 Sycorax silacea. — Mr. Gervase F. Mathew, R.N., communicated 

 a paper entitled "The Effect of Change of Climate upon the 

 emergence of certain species of Lepidoptera." A discussion 

 followed, in which Mr. Stainton, F.R.S., Mn Barrett Dr. 

 Sharp, F.R.S., and Mr. McLachlan, F.R.S., took part. 



Royal Microscopical Society, October 21. — Dr. R. 

 Braithwaite, President, in the chair. — The President said that 

 the pleasure with which he met the Fellows after the vacation 

 was very sadly marred by the death of one of their Secretaries, 

 Mr. John Mayall, Jun. The loss they had sustained was one 

 which the Society could hardly hope to replace, because per- 

 haps there was no living person who knew more about the 

 microscope and its applications than their deceased friend Mr. 

 Mayall. The difficulty in which they were placed had, however, 

 for the present been met by the kindness of Dr. Dallinger, who 

 had undertaken to fill up the vacant place until the end of the 

 current session. — Mr. A. D. Michael proposed, and Mr. T. H. 

 Powell seconded, that a special vote of thanks be given to Dr. 

 Dallinger for his kindness in accepting the office of Secretary. 

 The vote of thanks was carried by acclamation. — Mr. F. 

 Chapman read his paper on the Foraminifera of the Gault. — 

 Sir Walter J. Sendall exhibited and described a new apparatus 

 which he had devised for making accurate measurements with 

 the camera lucida, the inherent faults of which were explained 

 by drawings on the blackboard. Mr. E. M. Nelson said there 

 could be no doubt that camera lucida measurements when 

 made in the ordinary way as described were grossly incorrect, 

 and that the appajatus that had been devised was most ingenious 

 and thoroughly scientific in principle. He thought, however, 

 that there was a much simpler method of obtaining measure- 

 ments by projecting the image for a distance of 5 feet ; the curve 

 would with so large a radius be practically reduced to a straight 

 line. The camera lucida and neutral tint reflector were 

 only rough-and-ready means, and useful only for ready reference ; 

 where correctness was of importance, the eye-piece micrometer 

 would best meet the requirements ; the ruling of eye- piece 

 micrometers was now done so perfectly that it was possible to 

 arrive at measurements even as small as 1/500,000 of an inch 

 with far greater accuracy than could be attained with -any 

 machine. Dr. W. H. Dallinger thought there could be no 

 doubt of the value of the apparatus within certain limits, but it 

 would require great care for use with high powers, partly on 

 account of its weight if made in brass, as the specimen before 

 them ; perhaps it might be made in aluminium or some other 

 light material. The discussion was continued by Messrs. A. D. 

 Michael, C. Beck, and Sir Walter J. Sendall.— Mr. W. L 



