l82 



NATURE 



\yune 2 2, 1876 



In the Monthly Notices of the Royal Society of Tasmania for 



1874 occur some interesting abstracts of papers read before the 

 Society, including notices of the Angora goat, some species of 

 Tasmanian birds, introduction of the salmon into Tasmanian 

 waters, the Silurian fossils of Tasmania, the Tertiary basin of 

 Launceston, and a list of the plants of Tasmania, prepared in 



1875 by Baron Fred, von Mueller. To the notices are appended 

 the meteorological observations made during the year by Mr. F. 

 Abbott at Hobart Town, and by Mr. W. E. Shoobridge at 

 New Norfolk. From the monthly nofs we observe that 

 meteorological observations are also made at Port Arthur, Mount 

 Nelson, King's Island, and other places, and sent to the Society, 

 but the results are not published, nor so far as we are aware 

 have they been published since 1866. We hope the Society may 

 soon be in a position not only to publish these results, but also 

 results from a sufficient number of stations, so as to represent 

 adequately the meteorology of the island. 



The additions to the Zoological Society's Gardens during the 

 past week include a Cariama {Cariama cristata) frona South- 

 east Brazil, presented by Capt. W. C. Chapman, H.M.S. Zy/r/c? ; 

 two Black -eared Marmosets {Hepalc penicillata) from Brazil, pre- 

 sented by Mr. G. Newton ; a Rose-ringed Parakeet ( Pahcornis 

 docilii) from West Africa, presented by Mrs. Haywood ; a Hya- 

 cinlhine Maccaw {Ara hyacinlhina) from Brazil, presented by 

 Mr. II. Wilson ; a Moor Monkey {Seninopitheais inatiriis) from 

 Java, a Bay Antelope {CephaUphus dor salts) from West Africa, 

 purchased ; two Vulturine Guinea Fowl (Nu/iiuia viilturina) 

 from East Africa, a Puma {Fdis concolor) from Central America, 

 deposited. 



SCIENTIFIC SERIALS 



PoqgenJorff's Annalen der Physik und C/innu; No. 3. — Ac- 

 cording to the kinetic theory of gases, supposing the j;aie jus 

 molecule to consist of only one atom, the 1 elation of ihe two 

 specific heats (as Clausius has shown), would be i"666. The 

 lower number obtained by experiment for several gases may 

 probably be explained by the complex constitution of their 

 molecules. It seemed c^esirable to MM. Kundt and Warburg tj 

 determine cxperiraei)tally the .specific heat of mercury vapour, 

 which has been considered by chemists to cons'st of monatomic 

 molecules. Their method was to produce a sound in two glass 

 tubes placed end to end, and containing, the one mercury vapour, 

 the other air. Plaving introduced powder into the lubes, they 

 obstrved the distances between the nodes of vibration. Apply- 

 ing a formula of acoustics which comprehends, among other 

 things, the densities, the temperatures, and the relation of the 

 specific heats, and taking, as value of this relation in the case of 

 air, the number l'405, they ol>tain, for mercury vapour, the 

 number i"67, which maybe considered as fully in acord with 

 the number 1666 furnished by theory. — In an intereating paper 

 which follows, M. CoUey, of Moscow, examines a particular case 

 of work done by the galvanic current. Suppose a current to pass 

 through a vertical column of some salt, e.g. nitrate of silver ; both 

 electrodes being in this case of silver. In a given time a certain 

 c\uantity of silver is liberated and deposited. Now, if the current 

 pass up the column, it lifts this i^ilver against the force of gravity, 

 and so does mechanical work, which, in the opposite case (of the 

 current passing down) is not done. It appeared, then, as theory 

 anticipated, that the downward current in such a column (ais 

 measured by the galvanometer), was stronger than the upward, 

 and the difference was not greater than theory indicated. But 

 both with a battery current and with that from a Clarke mag- 

 neto-electric machine, it was considerably les?. The autho', 

 seeking an explanation, legards as untenable the general views 

 regarding passage of currents through liquid conductors, the 

 phenomena of passage from the .solid to the liquid conductor 

 being generally ignored ; and he thinks the facts favour Ilelm- 

 holtz's view, which regards the liquid, with the electrodes im- 

 mtr.-ed in it, as a condenser of very great capacity. Weak 

 carients which caimot pass through the liquid yet produce a 

 polarisation of the electrodes (charge of the condenser). With 

 strong currents the only difference is that as soon as the differ- 

 ence of tension has reached a certain limit (maximum of the 



electromotive force of polarisation), all newly arriving quantities 

 of electricity can unite through the liquid. M. Coliey shows 

 how his results are deducible from the state of things thus 

 supposed. — A number of experiments on electric clocks (with 

 Tiede's pendulum) are described by Dr. Joseph Brunn. — Of the 

 few remaining original papers we note one by M. Chwolson on 

 the theory of interference-phenomena. — A good experiment for 

 illustrating the explosive character of a mixture of oxygen and 

 hydrogen gases is described by M, Rosenfeld. 



Archives des Sciences Physiques et Naturelles, Jan. 15. — In the 

 opening paper of this number M. de CandoUe inquires into the 

 causes of unequal distribution of rare plants on the Alpine 

 chain (See Nature, vol. xiii. p. 516).— M. Favre fol- 

 lows with a note on the glacial and post-glacial strata of the 

 southern slope of the Alps, in the canton of Tessin and in Lom- 

 bardy. — M. Pictet discusses the application of the mechanical 

 theory of heat to the study of volatile liquids, and finds some 

 simple relations between the latent heat?, atomic weights, and 

 tension of vapours. — A series of meteorological observations 

 from the coast of Labrador, by Moravian missionaries, is com* 

 municated by M. Gautier (See Natuke, vol. xiii., p. 60). 



SOCIETIES AND ACADEMIES 

 London 



Royal Society, May 18. — "On the Organisation of the 

 Fossil Plants of the Coal-measures. — Part VIII. Ferns con- 

 tinued, and Gymnospermous Stems and Seeds." By Prof. W. 

 C. Williamson, F.R.S., Professor of Natural History, Owens 

 College, Manchester. 



The author described the stem of a new ftrn, in which the 

 principal vascular axis formed a cylinder enclosing a medulla, as 

 in some Lepidodendra. This vascular cylinder gives off secondary 

 bundle.-, to petioles, and rootlet?, and each vessel is filled. with 

 tylose. Two kinds of Fern-sporangia were described — one 

 Polypodiaceous, with a straight, vertical annulus; the other, with 

 the annulus horizontal and subterminal, exhibits a type seen in 

 the recent Schizeaceoe and Gleicheoiaceas. But the cluef subjects 

 of the memoir are the stems and seeds of Gymnosperms. Of 

 the former various modifications of the Stcrnbergian Dadoxylons 

 are de>cribed, and shown to correspond very nearly to many 

 iccent conifers, thourh with distinctive features of their own, 

 especially in the structure of their woody fibres, and in the leaf- 

 bundles of some species biing given off in pairs. The author 

 still excludes the Sigillarice fro;n the Gymnospermous group. 



The most important novelties are the (xymnospermous seeds, 

 exhibiting their internal organisation, found in France by M. 

 Grand- Eury, and by the author in this country. Of these he 

 describes a number of new genera and species in addition to the 

 Trigonocarpons previously described by Mr. Binney and Dr. 

 Hooker. Th'i most remarkable of these is one designated 

 Lagin.'stoim oroides, in which a large flask -shaped cavity, 

 inclosed within a crenulateJ canopy, occupies the apical end o 

 the s,ed, between the apex of the endosperm and the exostome. 

 Brongniart believed, with reason, that such cavities have origi- 

 nated in the absorption of the apex of the nucleus, leaving the 

 corresponding part of the nucular membrane to form the cavity 

 or "lagenosiome." In this lagcnostome large pollen-grains are 

 found in many cases. Brongniart designates it the " Cavite polli- 

 nique." Examples of several other seeds presenting generic and 

 sptcific modifications of the same type, as well as several species 

 of the well-known genus Cardiocarpum and of Trigonocarpum. 

 In all these the primary nucleus seems to have been absorbed, 

 being now only represented by the investing nucular membrane. 

 Within this is an inntr structureless bag, which, in some of the 

 Cardiocarpa, is filled with parenchyma, and which appears to 

 represent the secondary perispermic membrane, or what is really 

 the endospermic membrane, or primary embryosac of the Gym- 

 nosperms. The intimate structure of Trigonocarpum agrees with 

 Dr. Hooker's description of it so far as the longitudinal sections 

 are concerned, save that here, also, a " cavite pullinique " exists. 

 Transverse sections show that the well-known sandstone casts of 

 Trigonocarpum do not; represent the external form of these 

 fruits, but are casts of the interior of the hard endotesla. This 

 latter was not trigonous externally, like the common speci- 

 mens, but had twelve longitudinal ridges, three of which, corre- 

 sponding with those of the sandstone casts, were more prominent 

 than the rest. The endutesta was invested by a delicate paren- 

 chymatous sarcotesta. All these seeds appear to have Cycadean 



