140 



NATURE 



{June 7, 1888 



1888, No. I. — Some remarks on the consequences of the 

 earthquake of February 1887 in the Riviera, by H. Traut- 

 schold. — The chief noxious insects on tobacco in Bessarabia, an 

 elaborate research by Prof. K. Lindeman. (Both papers in 

 German.) — Count Alexis Razumovsky, first President of the 

 Society, by Dr.Benzengre (in French). — List of plants of Tambof, 

 by D. Litvinoff (continued). — On the hairs called auditive of the 

 spiders, by W. Wagner (Gekor-Organe of Dahl). They belong 

 to different types, and none of them can be recognized as per- 

 forming the auditive function ; they seem merely to be tactile 

 organs of a higher structure. — Studies on the palseontological 

 history of the Ungulatce, by Marie Pavloff (second memoir). 

 After having discussed the genealogy of the horse as viewed 

 by V. Kovalevsky, Messrs. Marsh, Cope, Lydekker, Branco, 

 and Schlosser, and discussed the rich material which Mrs. Pavloff 

 was in possession of, the writer arrives at the following scheme. 

 The eldest ancestors of the horse, Phenacodus, are found in the 

 Eocene of North America ; in Europe they are represented by 

 the Hyracotherium leporinum, which, together with the Pachyno- 

 lophus and Anchilophus, inhabited both continents. In the 

 Miocene we find the Anchit/urium, in America first, and later 

 on in Europe ; it was transformed in America into the Proto- 

 hippus of the Mio-Pliocene. This last gave rise to the 

 Hippidium and Equus, which largely developed during the 

 Pliocene period in America (E. parvulus), Asia (E. nomadicus), 

 Europe and Africa, where the E. stenonis was the ancestor of 

 the Post-Pliocene Equus caballus. In how far our present horse 

 originates from this later will be discussed next. Two plates 

 illustrate the paper, written in French. 



The Memoirs of the Odessa Society of Naturalists (vols, xi- 

 and xii. ) contain the usual quantity of elaborate work, especially 

 in anatomy and physiology. The papers on the embryogeny of 

 the fresh-water lobster, by M. Morin ; on the embryogeny of the 

 Caucasian scorpion Androctonus oimatus, by MM. A. Kovalevsky 

 and Shulghin ; on the development of the Urospora mirabilis, by 

 M. Woltke ; on the embryology of the Mysis chameleo, by M. 

 Nusbaum ; and on the morphology of the Haplotrichum roseum, 

 by M. Khmielevsky, are elaborate articles profusely illustrated 

 by excellent plates. — M. Krasilschik's researches on the struc- 

 ture and life of the Cercobodo laciniagerens — a new genus of the 

 Flagellatae — are most interesting, showing how this microscopic 

 organism preys on Bacteria and digests them, and how com- 

 plicated is its organization altogether. — The same author con- 

 tributes an interesting paper on the parasite Fungi of insects, and 

 M. Khawkin has an article on the buccal apparatus of the Eug'ena 

 and Astasia, as also on the laws of heredity in the case of uni- 

 cellular organisms ; and Dr. Kultchitsky studies the inte-tinal 

 canals of several fishes. — Geology and mineralogy are represented 

 by R. Prendel's article on the Wiluite, from which it appears 

 that the crystals of this interesting mineral have a double com- 

 position — those parts of it which penetrate into the depth of the 

 crystal as cones set upon the surfaces of the pyramids differing 

 both by their density and refractive power from the parts which 

 are built upon the faces of the prisms ; three papers by Prof. 

 Sintsoff on the water-bearing deposits of Kishineff, the Steppe 

 deposits on the left bank of the Lower Volga, and the Pliocene 

 of South Russia ; and on the crystalline rocks of Crimea, by M. 

 Prendel. — Prof. Klossovsky contributes a paper on the oscilla- 

 tions of temperature and density of the water of the Black Sea in 

 *the neighbourhoods of Odessa ; andMrs. Mary Balashoff has an 

 article on the influence of small ponds and of limited supplies 

 of water on the development of Planorbis. — Chemistry is repre- 

 sented by one paper, on the laws of dissolution of salts, by 

 R. Umoff. 



SOCIETIES AND ACADEMIES. 

 London. 



Royal Society, April 26.—" On the Occurrence of Alu- 

 minium in Certain Vascular Cryptogams." By A. H. Church, 

 M.A.,F.C.S. Communicated by Dr. J. H. Gilbert, F.R.S. 



Most of the older and more complete analyses of plant-ashes 

 disclosed the presence of sensible quantities of alumina. But of 

 late years this substance has been regarded as accidental, and 

 has been excluded from ash-constituents with the single exception 

 of certain species of Lycopodium. Since 1851 several analysts 

 have proved the presence of large quantities of alumina 

 in the ashes of these Dlants The author has confirmed and 



extended their remits, and has shown that the allied genus 

 Selaginella does not absorb alumina. He found, however, two 

 species of Lycopodium — namely, L. PhlegmaHa and L. biilardieri 

 —from which this constituent is absent. The anomaly was ex- 

 plained by the epiphytic nature of these plants, which have no 

 direct access to the soil. The author has further examined 

 certain species belonging to genera nearly related to Lycopodium, 

 such as Equisetum, Ophioglossum, Salvinia, Marsilea, and 

 Psilotum, in all cases with negative results. But he has found 

 20 per cent, of alumina in the ash of a New Zealand tree-fern, 

 and has also discovered abundance of this substance in Cyathea 

 medullaris and Alsophila australis, and more than mere traces 

 in Dicksonia squarro'a. The last part of the paper is occupied 

 with some considerations having reference to the connection 

 between elementary plant-food and the periodic law. 



May 17. — "On the Electromotive Properties of the Leaf of 

 Dioncea in the Excited and Unexcited States." No. II. By 

 J. Burdon-Sanderson, M.A., M.D., F.R.S. , Professor of 

 Physiology in the University of Oxford. 



The author has continued his experimental inquiries, of which 

 the results were communicated to the Royal Society under the 

 same title in 1881. In the introduction to the paper he gives 

 a summary of his previous observations, which led to the con- 

 clusion that the property by virtue of which the excitable 

 structures of the leaf respond to stimulation, is of the same 

 nature with that possessed by the similarly-endowed structures 

 of animals. He then proceeds to state that the main purpose of 

 his subsequent investigations has been to determine the relation 

 between two sets of phenomena which might, in accordance "with 

 the language commonly used in animal physiology, be termed 

 respectively those of the " resting current " and of the "action 

 current" of the leaf, i.e. between the electrical properties 

 possessed by the leaf when stimulated, and those which it 

 displays when at rest. Assuming the excitatory response in the 

 leaf to be of the same nature as the excitatory variation or 

 "action current" in muscle and nerve, the question has to be 

 answered, whether in the leaf the response is a sudden diminu- 

 tion of a previously existing electromotive action (according to 

 the pre-existence theory of du Bois-Reymond), or the setting up 

 at the moment of stimulation of a new electromotive action — in 

 short, whether and in how far the two sets of phenomena are 

 intef-dependent or the contrary. 



An observation recorded in his former paper suggested proper 

 methods. It had been shown that by passing a weak voltaic 

 current through the leaf for a short period in a particular 

 direction, its electromotive properties could be permanently 

 modified without loss of its excitability. If it could be shown 

 that the influence of this modification extended to both orders of 

 phenomena, those of rest and excitation, and that both underwent 

 corresponding changes of character under similar conditions, this 

 would go far to prove that an essential relation existed between 

 them. 



Acting on this suggestion, the author has had recourse to 

 modes of experiment similar to those which have been employed 

 during the last few years in the investigation of the newly-discovered 

 "secondary electromotive" phenomena of muscle and nerve (see 

 " Oxford Biological Memoirs," vol. i. part 2). The details of 

 these experiments, made in 1885, are given in the first three 

 sections of the paper. They relate to (1) the more immediate 

 effect of the current as seen in the records of successive galvano- 

 metric observations made at regular intervals; (2) the more 

 permanent influence of the current on the electromotive properties 

 of the unexcited leaf, and on its electrical resistance ; and (3) the 

 concomitant modification of its behaviour when stimulated. 



The general result of these experiments is to show that the two 

 orders of phenomena, the excitatory and those which relate to the 

 resting state, are so linked together that every change in the state 

 of the leaf when at rest conditionates a corresponding change in 

 the way in which it reacts to stimulation — the correspondence 

 consisting in this, that the direction of the response is opposed to 

 that of the previous difference of potential between the opposite 

 surfaces, so that as the latter changes from ascending to descend- 

 ing, the former changes from descending to ascending. 



The author considers that this can only be understood to mean 

 that the constantly operative electromotive forces which find their 

 expression in the persistent difference of potential between the 

 opposite surfaces, and those more transitory ones which are called 

 into momentary existence by touching the sensitive filaments or 

 by other modes of stimulation, have the same seat, and that the 



