394 



NA TURE 



\i>/'a}'. 14, 1S72 



derived therefrom ; by the action of nitric acid two substances 

 are obtained, allanic and allanturic acid. — A.n interesting paper 

 on a new series of aromatic hydrocirbons, by Zincke, folliw5 ; 

 by heating togetlier benjol, benzyl-chloride and zinc powder, or 

 finely divide! copper, a reaction sets in witli the evolution of 

 hydrochloric acid gas, and the partial formation of a metallic 

 chloride ; the principil reaction seems to b?, however, C-.H,C1 

 + C,;H|; = Cj^H,., 4-HCl. Benzyl-benzol is a solid crystalline 

 body, melting at 26' — 27", and boiling at 261° — 262" ; by oxida- 

 tion it is transformed into CjjHjnO, a crystalline bodybelonginj 

 to the monocUnic system, whic'i fuses at 26' — 26 •5°. Benzj- 

 pheno.i, hovever, has the same comoosition, brt crystallises in 

 the rhombic system, and fuses at 48° — 49° ; the body obtained 

 above is therefore an isomeric benzophenin, it, however, easily 

 pisses into the modification fusing at 48' — 49'. The cimpo;i- 

 tioi of benzyl-benzol will there ore probably be CfiHj — CHo — 

 C^Hj. — This number concludes with the translations of two 

 papers by Messrs. Friswell an! Armstrong respectively, which 

 have already appeared in the English journals. 



Ths Geological Magazim for January (No. 91) opens with a 

 paper on a subject connected with an important branch of 

 geology which is too much ne^lectel in this country, and, indeed, 

 has but few cultivators anywhere, namely, the miorosopic struc- 

 ture of the so-called igneous rocks. This is iVIr S. Allport's 

 notice of the microscopic structure of the pitchstones of Arrjn, 

 the appearance of the section; of which under ihe microscope is, 

 as described by Mr. AUport, exceedinjly beau':iful ; anl it is to 

 be hoped that this paper and the illustrationi accompanying it 

 miy induce others to enter upon this most interesting anl im- 

 p jrtant line of research. — The Rev. O. Fisher contributes a note 

 on " C'rquesand Tahises," with reference to Mr. Boiiney's paper 

 in the December number of the magazine Mr. Fisher ascribes 

 an esseitial part in the excavatioa of cii-ques to glacial action. — ■ 

 Mr. D. Forbes communicates a severe criticism of some remarks 

 made by Mr. A. H. Green in his account of the geology of part 

 of the county of Donegal. — "The Age of Floating Ice in North 

 Wales" is the subject of a paper by Mr. D. iMackintosh ; and 

 Mr. James Geikie publishes the second part of his " Memoir on 

 Changes of Climite during the Glacial Epjch." — The number 

 includes the usual notices and reviews. 



McniLiirts ill- la SocikS des Sciences Natiirelles de Cherbourg. 

 Tome XV. (Deuxieme Serie, Tome v.) 1870. "On the Swell 

 and Roll of the .Sea," by W. Bertin. — " N ites on the Comora 

 and Seychelles Archipelagos," by M. Jouan. These islands were 

 visited in 1S50; a very brief list of the flora and fauna is ap- 

 pended. The list of birds has been apparently overlooked in the 

 Zoological Record for January 1870 — " Notes on the Tubercles 

 met with in Callitriche aiilitinihilis" by M.M. Karelschtikoff and 

 Rosanoff, with a plate. — "On the Lopholiranchs," by M. Dumeril. 

 — "Notes of a Visit to Aden, Pomt de Galle, Singapore, and 

 Tche-fou," by M. Jouan. — " On the Influence of Climate on the 

 Growth of some Resinous Trees," by .M. Beketoff. — "Geologi- 

 cal Essay on the Department of La Manche," by M. Bonissent. 

 " Supplementary notes to a paper on the Swell and Roll of the 

 Sea," by M. Bertin. — Works received by the Society from July 

 1869 to August 1870. 



Proceedings of the Malnral History Society of Duhliii, for the 

 Session 1869-70, 1870-71, vol. vi., part i. (Dublin 1871) con- 

 tains the following papers by Dr. A. W. Foot : — i, Notes on 

 Irish Lepidoptera ; 2, On Goitre in .'\nimals ; 3, On the Breed- 

 ing of some Birds from the Southern Hemisphere in the Dublin 

 Zoological Gardens ; 4, Notes on Animal Luminosity; 5, Notes 

 on Entomology ; 6, Notes on Irish Diptera ; 7, On some Irish 

 Hymenoptera ; and the following by Mr. Wdliam Andrews : — 

 I, On the Inhabitants of the Rock-pools and caves of Dingle Bay, 

 records, as new to the fauna of Ireland, Aiptasia couchii, Stom- 

 phia ciiiirchiic, BalanopliyUia re;^iti, Capiiea ^lUigiiiiien, and " a 

 deep-water species of stony coral, formed by hydroid animals, and 

 related to the Tabulate Madrepores, which is nearly allied to, 

 and indeed considered identical with, Millepora alcicoriiis of 

 Linnreus ; " 2, Ichthyological Notes ; 3, On Orthagorisciis ob- 

 longiis, with two plates ; 4, On some rare Crustacea from the 

 south-west of Ireland ; 5, On the Ichthyology of the south- 

 west of Ireland ; b. Notes on Ilymenophylla, especially 

 with reference to New Zealand species ; 7, On some Irish Saxi- 

 frages ; also papers by Prof Macalister, on the mode of growth 

 of Discoid and Turbinated shells ; by G. H. Kinahan, on the Ferns 

 of West Connaught and the south-west of Mayo, 



SOCIETIES AND ACADEMIES 

 London 



Royal Society, March 7. — "On the organisation of the 

 Foisil Plants of the Coil-measures. — Part III. Lvcopodiace.e." 

 By Prof. VV. C. Williamson, F. R. S. An outline of the subject 

 of this memoir has aU'eady been published in the Proceedings 

 in a letter to Dr. Sharpey. In a former memoir the author de- 

 scribed the structure of a series of Lepidodendroid stem?, appa- 

 rently belonging to different genera and species. He now 

 describes a very similar series, but all of which, there is strong 

 reason for believing, belong to the same plant, of which the 

 structure has varied at different stages of its growth. The speci- 

 mens were obtained from some thin fossiliferous deposit; dis- 

 coveref by Mr. G. Grieve, of Burntisland, in Fifeshire, where 

 they occur imb-dded in igneous rocks. The examples vary from 

 the very youngest half-developed twigs, not more than ,-'jth 

 of an inch in diameter, to arborescent stems having a circum- 

 ference of from two to three feet. The youngest twigs are com- 

 pjsed of ordinary parenchyma, and the imperfectly developed 

 leaves which clotlie them externally have the same structure. In 

 the interior of the twig there is a single bundle, consisting of a 

 limited number of barrel vessels. In the centre of the bundle 

 there cm always be detected asmall amount of primitive cellular 

 tissue, which is a rudimentary pith. As the twig expanded into 

 a branch, this central pith enlarged by multiplication of its cells, 

 and the vascular bundle in like manner increased in size through a 

 correspondingincreasein the number of its vessels. Thelatterstruc- 

 ture thus became converted into the vascular cylinder so common 

 amongit Lepidolenlroid plants, in transverse sections of which 

 the vessels do not appear arranged in radiating series. Simulta- 

 neously with these chinges the thick parenchymatous oute- layer 

 becomes differentiated. At first but two layers can be distinguished 

 — a thin inner one, in which the cells have square ends, and are 

 disposed in irregular vertical columns, and a thick outer one con- 

 sisting of parenchyma, the same as the epidermal layer of the 

 author's precedmg memoir. In a short time a third layer was 

 developed between these two. 



When the vascular cylinder had undergone a consider.able in- 

 crease in its size and in the number of its vessels, a new element 

 made its appearance. An exogenous growth of vessels took 

 place in a cambium layer, which invested the pre-existing vascu- 

 lar cylinder. The author distinguishes the latter as the vascular 

 medullary cylinder, and the former as the ligneous zone. The 

 newly-added vessels were arranged in radiating laminx, separated 

 froin each other by small but very distinct medullary rays. At 

 an earlier stage of growth traces of vascular bundles proceeding 

 from the central cyhnder to the leaves had been detected. These 

 are now very clearly seen to leave the surface of the medullary 

 vascular cylinder where it and the ligneous z )ne are in mutual 

 contact ; hence tangential sections of the former exhibit no traces 

 of these bundles, but similar sections of the ligneous zone present 

 them at regular intervals and inlquincuncial order. Each bundle 

 passes outwards through the ligneous zone, imbedded in a cellular 

 mass, which corresponds, alike in its origin and in its direction, 

 with the ordinary medullary rays, differing from them only in its 

 larger dimensions. At this stage of growth the plant is obviously 

 identical with the Diploxyloii of Corda, with the Anabathra of 

 Witham, and, so far as this internal axis is concerned, with the 

 Sigillaria elcgans of Brongniart. The peculiar medullary vascu- 

 lar cylinder existing in all these plants is now shown to be merely 

 the developed vascular bundle of ordinary Lycopods, wliilst the 

 exogenous radiating ligneous zone enclosing that cylinder is an 

 additional element which has no counterpart amjngst th; living 

 forms of this group. 



Though the central compound cellulo-vascular axis continued 

 to increase in size with the general growth of the plant, it was 

 always small in proportion to the size of the stem. The chief 

 enlargement of the latter was due to the growth of the bark, 

 which e.xhibited three very distinct layers, — an inner one of cells 

 with square ends, and slightly elongated vertically and arranged 

 in irregular vertical rows, an intermediate one of prosenchyma, 

 and an outer one of parenchyma. These conditions became yet 

 further modified in old stems. The exogenous ligneous zone 

 became very thick in proportion to the medullary v.ascular 

 cylinler, and the differences between the layers of the bark 

 became yet more distinct. These differences became the most 

 marked in the prosenchymatous layer ; at its inner surface the 

 cells are prosenchymatous, but towards its exterior they become 

 yet more elongated vertically, their ends being almost square, 



