July I, 1875] 



NATURE 



179 



SOCIETIES AND ACADEMIES 

 London 



Linnean Society, June 17. — Dr. G. J. Allman, F.R. S., 

 president, in the chair. — Mr. J." E, Howard, F.R.S., made 

 some observations on Cinchoua anglica, a hybrid between C. 

 Calisaya anA C. si4cdru/»a.^Y)v. Pryor exhibited specimens of 

 Myrsiru- Urvillei, from New Zealand, which appeared to be hardy 

 in this country. — The following papeis were read: — i.On the 

 affinities and febrifuge properties of the Aristolochiacea;, by Mr. 

 Clark. - 2. On Whitfieldia, by Mr. S. Moore. — 3. On the anatomy 

 o( AtnpJiioxus, by Prof. E. R. Lankester, F. R.S. The author 

 described the anatomy of .-^. lanceolatiis as worked out in a series of 

 sections made from numerous specimens collected by him at 

 Naples. In opposition to Stieda, the truly perforate structure of 

 the pharynx was asserted. A true body cavity or coelom, distinct 

 from the atrial chamber, was described, and it was shown to ex- 

 pand and attain a large development in the post-atrioporal region 

 of the body. A pair of pigmented canals were described, apparently 

 representing the vertebrate renal organ in a degenerate or else a 

 rudimentary condition. Johannes Midler's pores of the lateral 

 canals were shown to be hyoid slits leading into the pharynx. 

 The attachment of the pharyngeal bars to the wall of the atrium 

 by a series of pharyngo-pleural septa was minutely described. 

 It was further shown that the marginal ridges of the ventral sur- 

 face (metapleura) are hollow, containing a lymph-space, and 

 that they, as well as the plates of the ventral integuments, disap- 

 pear when the atrial chamber is largely distended with the 

 sexual products. Drawings by Mr. W. J. Fanning, of Exeter 

 College, were exhiLited in illustration of the above statements. 



Physical Society, June 26. — Prof. G. C. Foster, vice-presi- 

 dent, in the chair. — ^Ir. W. J. Wilson read a paper on a method 

 of measuring electrical resistance of liquids. Great difficulty has 

 hitherto been experienced in measuring the resistance of electro- 

 lytes on account of the polarisation of the electrodes, and most 

 of the methods hitherto employed have aimed at reducing this 

 to a minimum by using large electrodes and very weak or rapidly 

 alternating currents. The determinations, however, are difficult 

 and require to be quickly performed. The following method is 

 easy and is free from both the above objections. The arrange- 

 ment in its most simple form consists of a long narrow trough 

 filled with the liqnid to be measured, say dilute acid. A porous 

 pot containing a zinc plate in sulphate of zinc being placed in 

 the acid at one end of the trough, and a similar pot with a 

 copper plate in sulphate of copper in the acid at the other end, 

 the whole arrangement forms a sort of elongated Daniell's cell, 

 the chief resistance of which is in the long column of acid. The 

 circuit between the plates being completed through a resistance 

 box and mirror galvanometer, the current is shunted until a 

 suitable deflection is obtained. One of the porous pots is now 

 moved along the trough towards the other, and, as the resistance 

 of the circuit is thus reduced by shortening the column of acid, 

 the galvanometer deflection largely increases. The external 

 resistance is now increased by means of the box, until the deflec- 

 tion is reduced to the same point as at first. This resistance put 

 into the circuit is evidently equal to that of the liquid taken out, 

 and thus a measure of the liquid resistance is obtained. Two 

 forms of apparatus were shown. In one, the vessels containing 

 sulphate of zinc and sulphate of copper respectively, formed 

 pistons in a glass tube which contained the liquid to be examined. 

 In the other, two pairs of concentric vessels were connected by 

 a bent glass tube which contained the liquid under examination. 

 The method is applicable to a great variety of liquids, and with 

 care almost any degree of accuracy may be obtained. The chief 

 obstacle to exact measurements lies in the fact that the resistance 

 of liquids is greatly affected by temperature, but this difficulty is, 

 of course, common to all methods. Mr. Wilson has been expe- 

 rimenting with brine, and gave some of the results obtained, but 

 he has not as yet made a sufficient number of experiments to 

 complete a table. A mode of arranging the apparatus in a dif- 

 ferential or bridge form was also described, but it has not been 

 found necessary to use it ; the simple circuit arrangement giving 

 accurate results with less trouble. Prof. Foster asked whether 

 experiments had been made in order to compare this method 

 with Wheatstone's, which differed from Mr. Wilson's, as liquid 

 electrodes were not used. He then described an arrangement 

 he had adopted for measuring the polarisation of plates in a 

 voltameter. Prof M'Leod stated that he had used plates of 

 amalgamated zinc and reversed currents to overcome polarisation. 

 He found that some salts, chloride of zinc for instance, had points 



of maximum conductivity which corresponded to a definite degree 

 of concentration. Prof. Guthrie considered the research to be 

 interesting as showing that points of minimum resistance might 

 coincide with points of definite hydration of the salts. — Mr. 

 Wilson, replying to Prof. Foster, stated tha tthe chief objection 

 to the use of metal plates is not a variation of the electromotive 

 force of polarisation, but the accumulation of bubbles of 

 gas on the metallic surfiices.— Dr. Stone made a communication 

 on the subjective phenomena of taste. He stated that some 

 experirnents he had recently made led him to consider whether 

 there might be " complementary taste," just as there is "comple- 

 mentary sight." He described the following experiments as 

 examples of the kind of phenomenon. If water be placed in 

 the mouth after the back of the tongue has been moistened with 

 moderately dilute nitric acid, the water will have a distinctly 

 saccharine taste. Or if the wires from a lo-cell Grove's battery 

 be covered with moist sponge, and placed one on the forehead 

 and the other at the back of the neck, an impression is produced 

 which is exactly similar to that resulting from the insertion of 

 the tongue between a silver and a copper coin, the edges of which 

 are in contact. Dr. Stone showed that the induced current 

 usually employed for medical purposes has not this effect, and 

 he considered the results curious, as, so far as we know, they can 

 hardly be the result of chemical action. Mr. Roberts mentioned 

 an instance in which sudden alarm had been followed by the 

 peculiar taste which results from the introduction of two coins 

 into the mouth, to which allusion had already been made. — Prof. 

 Foster thanked Dr. Stone in the name of the Society, and 

 expressed a hope that he would continue his suggestive and im- 

 portant experiments. — Four other communication:, were made, 

 of which abstracts will be given in a future number. 



Entomological Society, June 7.— Sir Sidney S. Saunders, 

 C.M.G., president, in the chair. — Mr. Briggs exhibited some bred 

 specimens of Zyqana vuliloti, bearing a strong resemblance to Z. 

 trifolii, and mentioned several in.^tances in which the offspring of 

 Z. /«^/i7c>/i exhibited a taint of trifolii h\oo6i, and suggesting that 

 Z. fueliloti might be only a stunted variety.— Mr. M'Lachlan exhi- 

 bited a portion of a vine-leaf on which were galls of Phylloxera 

 vastairix, the leaf having been plucked in a greenhouse near 

 London. — The Rev. A. E. Eaton exhibited the insects which he 

 had recently captured in Kerguelen's Island. There were about 

 a dozen species belonging to the Coleopiera, Lepidoptera, and 

 Diptera, besides some specimens of bird-lice and fleas. They 

 were all either apterous or the wings were more or less rudi- 

 mentary. One of the Diptera possessed neither wings nor 

 halter es. — Mr. Briggs exhibited a specimen oi Halias prasinaua, 

 which, when taken, was heard to squeak several times distinctly, 

 and at the same time a slender filament projected from beneath 

 the abdomen was observed to be in rapid motion, and two small 

 spiracles close to the filament were distinctly dilated. — The 

 President called attention to a larva which he had recently dis- 

 covered at Reigate in the body of a stylopised female of Andrena 

 tnmmerana, the larva having a long telescopic process at the 

 anterior extremity, and two reniform processes behind, similar to 

 Conops, an insect which had frequently been reared from Poni' 

 piliis, Sphex, and Odyiterus, and had also been met with in 

 Bombus, although he had never before heard of its being found 

 in Andrena. — The Secretary exhibited some specimens of a 

 minute Podura forwarded to him by the Secretary of the Royal 

 Microscopical Society, having been found on the snow of the 

 Sierra Nevada in California. — Mr. F. H, Ward exhibited some 

 microscopic slides showing specimens of a flea attached to the 

 skin of the neck of a fowl. — Prof Westwood communicated a 

 description of a new genus of Clerideous Coleoptera from the 

 Malay Archipelago. — Mr. M'Lachlan read a paper entitled "A 

 sketch of our present knowledge of the Neuropterous Fauna of 

 Japan (excluding the Odonata and Irichoptera)," 



Berlin 

 German Chemical Society, June 14. — A. W. Hofmann, 

 president, in the chair. — The President opened the proceedings 

 by informing the Society that their veteran honorary member. 

 Prof. Wbhler, had very kindly written some recollections of his 

 li.'e for the special purpose of being read to the meeting ; refusing, 

 however, their publication in the Proceedings of the Society. 

 The tollowing short extracts of these " recollections of an old 

 chemist " will give some idea of the interest attending the 

 MS. read by the President. On the 2nd of September, 1823, 

 Dr. Wohler had finished his ftiedical. studies at Heidelberg, 

 and, yielding to the advice of L. Gmelin, he abandoned the plan 



