June 17, 1897] 



NATURE 



167 



form of laccolites, and were not anticlinal folds which havp 

 afterwards been affected by cross-folds. The domes were con- 

 trasted with igneous peaks which occurred in abundance in a 

 different part of the area, usually at a higher horizon of the 

 strata and at a higher level above sea. These were probably 

 volcanic pi|>es through which the lava was forced and extruded 

 at the surface. The author compared the rocks of the bosses 

 with those of the dykes and flows. Both were principally per- 

 fectly fresh dolerites, but the former were distinguished by the 

 presence of intergrowths of micropegmatite as the last stage of 

 consolidation, as in the " Konga diabases." There was also 

 among them a felsite-breccia with micropegmatite developed in 

 the cracks. He considered that nearly all the igneous rocks of 

 Cutch had been derived from a single magma, which in a solid 

 condition must have contained large crystals of augite, olivine, 

 and ilmenite in a ground-mass of lime-felspars, and have been 

 throughout of a basic character. Such a magma originated in 

 more than one centre. 



Zoological Society, June i.— Dr. Albert Giinther, F.R S., 

 \'ice- President, in the chair. — A connnimication was read from 

 Dr. John Anderson, F.R.S., containing a water-colour drawing 

 of the Egyptian weasel {Mustela stibpalma/a), taken from living 

 specimens which he had recently presented to the Society's 

 menagerie. Dr. Anderson also sent some remarks on this rare 

 Egyptian mammal, and others were made by Mr. E. C. Taylor. 

 — A communication was read from Prof. T. W. Bridge, on the 

 morphology of the skull in the Paraguayan Lepidosiren and 

 other Dipnoi. — A -paper on the classification of the Thyrididie, 

 a family of the Lepidoptera Phalsenae, by Sir George F. 

 Hampson, Bart., was read. It contained short diagnoses of the 

 twenty-six known genera (of which Pycuosonia and Plagiosella 

 were described as new) of the group, and a list of the known 

 species of each genus.— A second communication from Sir 

 George Hampson treated of the classification of the 

 ChrysaiigitKc, a subfamily of moths of the family Pyralida. 

 Like the preceding paper, it contained diagnoses of the 

 known genera, of which seventy-six were enumerated, and 

 a list of the known species of each genus. Of the genera the 

 following were characterised as new -.—Hyaloslicta, Protruhia, 

 Prionidia, Microzancla, Sarcistis, Monoloxis, Dilaxis, Tetra- 

 schistis, and Cyclopalpia. — Dr. A. G Butler read a paper on a 

 collection of Lepidoptera obtained in East Africa in 1894 by Mr. 

 F. Gillett. Fifty-seven species were enumerated, and the dates 

 of the capture of the specimens were recorded. — Dr. C. L 

 Forsyth Major read a paper on the Malaga.sy genus of rodents 

 Brachyiiromys, and entered into the question of the mutual 

 relation of some of the groups of the Ahiridic {Hesperoiiiyime, 

 MicrotitiiT, Murina, and Spalacida) with each other and with 

 the Nesomyiiue of Madagascar. The Malagasy Rodentia were 

 considered as forming a subfamily Nesomyiuic, the lowest of 

 Muridcc, being forerunners of the American Hesperomyina, 

 the Old-World Mitrints and the Microtiiuv {Arvicolina). One 

 of the genera from Madagascar {Brachyuroinys) was stated to 

 bear close affinities to a genus of the Spalacida. Reasons were 

 given for regarding the last-named family as only lowly- 

 organised Miiridcc. 



Cambridge. 



Philosophical Society, May 10.— Prof. Liveing, Vice- 

 President, in the chair. — Observations on stomata by a new 

 method, by Mr. Francis Darwin, President. The method con- 

 sists in the use of " Chinese sensitive leaf," i.e. thin sheets of 

 horn treated in a special manner. When a strip of this substance 

 is placed on the stomatal surface of a leaf, it gives evidence of the 

 condition of the stomata by its movement. If they are open, it 

 curves away from the source of moisture ; if shut, it remains 

 stationary. By means of a simple apparatus the degree of curva- 

 ture of the horn is recorded. All the ordinary experiments with 

 stomata can be easily and rapidly shown with a hygroscope of 

 this sort. By taking readings at regular intervals the diurnal 

 course of the stomata can be studied ; in this way it has been 

 shown that the nocturnal closure of the stomata is a periodic 

 phenomenon like the " sleep " of leaves. A number of observa- 

 tions were made on the effects of the withering of leaves on the 

 stomata : it was shown that while the stomata of certain species 

 simply close as the leaf withers, in others the first effect is a 

 well-marked opening. This fact is of interest in connection with 

 the mechanism of the stomata, since it indicates the share which 

 the pressure of the surrounding epidermic cells has on the guard 

 cells. It was shown that many plants open their stomata in 



NO. 1442, VOL. 56J 



long-continued darkness ; this fact bears on the mode of action 

 of the guard cells, since it shows that they do not (as is often 

 assumed) lose their turgescence when the as.similation of CO.^ is 

 prevented. — Notes on hybrid Cinerarias produced by Mr. Lynch 

 and Mi.ss Pertz, by Mr. Bateson. It is stated by many writers 

 that the garden Cineraria arose as the hybrid offspring of several 

 species of Senecio from the Canary Islands. This statement has 

 been questioned by Mr. Thiselton Dyer on various grounds. 

 The author exhibited hybrids raised from .S". emeritus, S. multi- 

 Jlorus, and S. Ileritieri ( = ianaius) raised in the Cambridge 

 Botanic Gardens by Mr. Lynch and Miss Perlz, which illustrated 

 the very great variability which appears in the offspring of the 

 various crosses In particular, specimens of Heritieri 9 x cruentus 

 S and of the reciprocal cross were produced, showing excessive 

 variability and proving how greatly the peculiar characters of 

 Heritieri may be obscured in the offspring, even of the first 

 cross. Five specimens of nittltijloriis ^ < Heritieri S were ex- 

 hibited, each of which was exceedingly distinct from the rest. 

 Experiments had entirely confirmed Darwin's observation that 

 Cinerarias are self-sterile in a high degree. They hybridise, on 

 the contrary, with great readiness. An accidental hybrid 

 between Heritieri 'i x garden Cineraria (J and the reciprocal 

 wore also shown, the two plants being quite unlike each other. 

 One seedling inultiflorus 9 x garden Cineraria i had been pro- 

 duced which was almost entirely female, a few anthers only ap- 

 pearing in later inflorescences. These experiments were to be 

 continued ; but so far as they had gone, they were entirely con- 

 sistent with the view that the Cineraria was a hybrid between 

 several species, cruen/tts, Heritieri and, probably, imiltiflortis 

 being among them. The two first are named by most writers as 

 probable parents. 



Paris. 

 Academy of Sciences, June 8. — M. A. Chatin in the chair.— 

 On the periods of double integrals, and the development of the 

 disturbance function, by M. H. Poincare. — General theory of 

 gradually varied conditions in the friction of liquids with 

 vortices ; forniulse of the first approximation, by M. J. Bous- 

 sinesq. — Action of light upon mixtures of chlorine and hydrogen, 

 by MM. Armand Gautier and H. Helier. The influence of 

 moisture upon the combination of the two ga.ses under the 

 action of light was first studied. When water is present the 

 velocity with which hydrochloric acid is formed is considerably 

 increased, this effect being probably produced by the lowering 

 of the partial pressure of the hydrogen chloride produced. The 

 effect produced by exposure for different periods to standard 

 artificial light was also studied. If either gas is in excess, the 

 reaction is much accelerated. — Observations on the limitation 

 of chemical reactions, with especial regard to the preced- 

 ing communication, by M. Berthelot. — Reply of M. Armand 

 Gautier to M. Berthelot. — Note by M. Berthelot accom- 

 panying the presentation of his work on " Therm<w:himie." 

 — A new truffle {^Terfezi aphroditis) from the Isle of Cyprus, by 

 M. Ad. Chatin. This truffle is characterised by its dark colour, 

 being kncjwn locally as the black truffle. It frequently attains a 

 very large size, one weighing 385 grams having been found in 

 1873. — Micronietric measures of double stars made at St. 

 Petersburg and Domkino by Prof. S de Gla.senapp, Director of 

 the Imperial University of St. Petersburg, by M. I^ewy. — 

 Examination of .some spectra, by M. Lecoq de Buisbaudran. A 

 reply to some criticisms of Eda and Valenta. — A Committee was 

 appointed to present a list of candidates for the Foreign 

 As.sociateship, rendered vacant by the death of M. Tchebychef. 

 —Theoretical and practical study of the lung, its functions and 

 diseases. Tuberculosis and its clinical cure, by M. H. Grasset. 

 — On surfaces having the same spherical representation, by M. A. 

 Pellet. — Remarks on a recent note of J. M. Weber, by M. E. 

 Goursat. — On real systems of complex numbers, by M. E. Cartan. 

 — Properties of the simple kathodic rays. Relations with simple 

 electric oscillations, by M. H. Deslandres. An electrified body, 

 interposed in the path of a kathode ray, causes an enlargement 

 of the shadow, the kathode bundle being divided up into several 

 distinct and unequally deviated bundles. These bundles are 

 called simple kathodic rays, and it is shown that they correspond 

 to simple electric oscillations.— On the atomic weight of cerium, 

 by MM. Wyrouboff and A. Verneuil. Having shown in a pre- 

 ceding paper that it is possible to prepare cerium oxide in a 

 state of high purity, this specimen has been utilised to fix the 

 atomic weight of the metal. The sulphate was carefully purified 

 from free sulphuric acid by repeated precipitation with alcohol 

 or by careful ignition, and the atomic weight determined by 



