Ai'RiL 9, 1 903 J 



NA TURE 



55i 



by Messrs. Crossley and Haas. A description of the deri- 

 vatives obtained by the action of phosphorus tri- and penta- 

 chlorides on dihydroresorcinol. — The constitution of cotar- 

 nine, by .Messrs. Dobbic, Lauder and Tinkler. The 



authors have examined the ultra-violet absorption spectra 

 of solutions of this alkaloidal derivative in various solvents 

 in order to ascertain which of the three formulae assigned 

 to the base most probably represents its constitution ; the 

 observations show that in the solid state cotarnine has the 

 formula a, and that on solution in alcohol is converted into 

 the coloured isomeride having the formula b. 



CH.OH— NMe 



a I 

 X CIL CH„ 



CII==NMe.OH 



-> C 8 H e O 3 <e 



— Decomposition of mercurous nitrite by heat, by Dr. P. C. 

 Ray and Mr. J. N. Sen. The products of this reaction are 

 mercuric nitrate, metallic mercury, nitric oxide and peroxide. 

 — The action of nitrogen tetroxide on pyridine, by Mr. J. F. 

 Spencer. The first product of this reaction is a molecular 

 additive compound, but eventually there is formed a yellow 

 substance of the composition (C 3 H 4 0,N„),, and a purple 

 product of still more complex constitution. 



Entomological Society, March 18.— Prof. E. B. Poulton, 

 F.R.S., president, in the chair. — The Rev. F. D. Morice 

 exhibited with drawings a dissected gynandromorphous speci- 

 men of a bee (Ostnia fulviventris, Panz.). — Mr. A. Bacot 

 exhibited a number of specimens of Malacosoma neustria x 

 castrensis in various stages, including a series of six cJ cf 

 and sixteen 9 9 imagines reared during 1902 from one 

 batch of ova laid by a Q Castrensis, which had been mated 

 with a c? Neustria, and two 9 9 reared from another batch 

 of ova the result of a similar cross ; also blown larvae of 

 hybrid parentage, and twigs showing attempts at oviposit- 

 ing on the part of 9 9 hybrids that had paired with hybrid 

 d <S of the same brood ; also a series of M. Neustria, M. 

 Castrensis and the hybrid moths reared during 1901 for 

 comparison. — Mr. H. St. J. Donisthorpe exhibited speci- 

 mens of Trimium brevicorne, Reich., from Chiddingfold, 

 Surrey, an unusually southern locality for this species. — Mr. 

 C. P. Pickett exhibited specimens of Hybernia leucophaearia 

 and Phigalia pedaria taken at Chingford on February 14, and 

 ova of Endromis versicolora on birch twigs, laid March 16. 

 — Mr. G. C. Champion exhibited a long series of specimens 

 of a species of Cneorrhinus (? pyriformis) from Piedrahita, 

 Spain, and called attention to the great dissimilarity between 

 the sexes, and also to the possibility of the females being 

 dimorphic, one form clothed with green scales, and the 

 cither with grey scales like the male. He also exhibited 

 Dorcadion dejeani, Chevr., from the Sierra de Bejar, a 

 species peculiar to that district. — Mr. R. McLachlan, 

 F.R.S., exhibited a dragonfly belonging to a small species 

 <if the genus Orthetrum, attacked by a fly almost as large 

 as itself of the family Asilida;, taken in Persia in June, 1902, 

 by Mr. H. F. Witherby. The fly had inserted its proboscis 

 at the junction of the head and prothorax, a vulnerable point. 

 He also exhibited a female specimen of a large /Eschnid 

 dragonfly, Hemianax cpliippigcr, Burm., captured in a street 

 at Devonport on February 24. The species occasion- 

 ally visits Europe in migratory swarms or sporadically, but 

 is especially African, and its presence at Devonport in 

 February might probably be due to the example having 

 flown on board a vessel off the African coast. Mr. F. 

 Merrifield suggested that there might be some connection 

 between the appearance of the insect in England and the 

 reported showers of fine dust which are generally supposed to 

 have come from the Sahara. — Prof. E. B. Poulton, F.R.S., 

 exhibited seasonal forms of Precis antilope, parent and off- 

 spring, bred by Mr. G. A. K. Marshall in South Africa, and 

 Precis coelestina, from the Victoria Nyanza region, with the 

 dry-season form of that species, now taken probably for the 

 first time. — Mr. W. J. Lucas exhibited with the lantern a 

 slide showing the larva of Cossus ligniperda in its gallerv 

 in a tree trunk. — Dr. T. A. Chapman exhibited with the 

 lantern a series of slides illustrating the life-history of 

 Liphyra brassolis, Westw., a Queensland species, the larva 

 of which lives in ants' nests, and feeds upon the ant-larva-. 

 The imago on emergence from the pupa is clothed with 

 scales highly distasteful to the ant, which protect it during 

 emergence from attack, and until such time as it is able to 



NO. 174.5, VOL. 67] 



fly, when they drop off. — Mr. G. C. Champion read a paper 

 on an Entomological Excursion to Bejar, Central Spain. — 

 Dr. F. A. Dixey read a paper, illustrated by lantern slides, on 

 Lepidoptera from the White Nile, collected by Mr. W. L. S. 

 Loat ; with further notes on seasonal dimorphism in butter- 

 flies. — Mr. E. Saunders, F.R.S., communicated a paper on 

 Hymenoptera Aculeata collected by the Rev. A. E. Eaton in 

 Madeira and Teneriffe, in the spring of 1902. 



Royal Microscopical Society, March iS. — Dr. H. 

 Woodward, F.R.S., in the chair. — Mr. J. W. Gordon gave 

 an account of his paper on the Helmholtz theory of the 

 microscope, which contained a rough sketch of the theory 

 of diffraction, and considered this from a new point of view, 

 expanding the Helmholtz theory from this position. The 

 paper then dealt with the Helmholtz theory, starting with 

 the proof of the sine law as given by Helmholtz. Having 

 proved the sine law, Helmholtz made deductions from it, and 

 drew the inference that the resolving power of the most 

 perfect optical system must necessarily stop short at an 

 object which was less than half a wave-length of the light 

 by which its observation was attempted. Mr. Gordon then 

 proceeded to set out the points of his own paper, including 

 a description of some vibrating screens by the aid of which 

 the definition of high powers was much improved, when the 

 image was greatly super-amplified by eye-piece magnifica- 

 tion. 



Linnean Society, March 19.— Prof. S. H. Vines, F.R.S., 

 president, in the chair. — Mr. Clement Reid exhibited draw- 

 ings by Mrs. Reid of fruits and seeds of British pre-Glacial 

 and inter-Glacial plants (Thalamiflora;). In each case the 

 specimens illustrated were the earliest known representatives 

 of the species. Most of the plants are still living in Britain ; 

 but among the Thalamiflorae from the Cromer Forest-bed 

 occur seeds of Hypecoum, a genus specially characteristic 

 of the Mediterranean region, and no longer found living 

 nearer than Southern France. The fossil seeds correspond 

 closely with the living Hypecoum pendulum of Southern 

 France, and either belong to that species or to a closely- 

 allied extinct form. The seeds of all the species of Hypecoum 

 are covered by a curious close mosaic of cubic crystals, 

 apparently calcium oxalate, which fill square pits in the 

 surface of the testa. Traces of these pits are still found 

 on some of the fossil seeds. — Mr. G. Claridge Druce read 

 a paper on Poa laxa and Poa stricta of our British floras. 

 For some years past, doubts have been expressed by critical 

 botanists as to the correct naming of these two plants. The 

 author's conclusions are, that the plants named Poa alpina, 

 var. acutifolia, and P. laxa, var. scotica, have been mis- 

 understood and variously named ; he therefore gives detailed 

 descriptions of these two plants, with synonymy so far as 

 British floras are concerned. The paper was illustrated 

 by specimens from the author's herbarium, and the type- 

 specimen of Poa flexuosa from Smith's herbarium. — The 

 botany of the Ceylon patanas, part ii., by Messrs. J. Parkin 

 and H. H. W. Pearson. In a former paper on the same 

 subject (Pearson, Joitrn. Linn. Soc. Bot., vol. xxxiv. 1899, 

 pp. 300-365) the main features of these grassy uplands, 

 locally known as "patanas," were given, the probable 

 causes which have led to their development discussed, and 

 the general biological characters of their flora described. 

 An account of the anatomical examination of the plants 

 collected was promised for a separate paper; this com- 

 munication is the fulfilment of the promise. 



Paris. 

 Academy of Sciences, March 30. — M. Albert Gaudry in 

 the chair. — On affinity at low temperatures; the reactions 

 of liquid fluorine at —187° C, by MM. H. Moissan and 

 J. Dewar (see p. 544). — On the alkyl- and acyl-cyano- 

 camphors and the alkylcamphocarbonic esters. The in- 

 fluence of the double linkage of the ring contain- 

 ing asymmetric carbon on the rotatory power of 

 the molecule, by M. A. Haller. The enolic and 

 ketonic forms are simultaneously produced in the 

 formation of derivatives of cyanocamphor, which are dis- 

 tinguished by their behaviour on treatment with hydro- 

 chloric acid. Measurements of the rotatory power showed 

 that higher values were always given by the enolic forms than 

 with the ketonic forms. — Problems in biological energetics, 

 raised by a note of Lord Kelvin on the regulation of the 



