53° 



NATURE 



[April i, 1880 



immediately succeeding the Archncans ." is discussed in connec- 

 tion with the facts that calcareous organisms are rare or not 

 present in the formation referred to, and that calcareous rocks 

 are abundant in the preceding systems— the Archseans. These facts 

 are held to be innnisonwith the authors' conclusions stated in the 

 last chapter, and to favour the view that the Archjean limestones 

 with their present constitution were not available as materials 

 for the production of calcareous rocks in the earliest Cambrian 

 age. 



(K) " The genetic difference between mineralised and methy- 

 losed metamorphism " is explained by assuming that water has 

 been an important factor in both cases ; but as the minerals in 

 the first group are for the most part anhydrous or dry species, it 

 is assumed that the original (? hygroscopic) water, which its 

 members contained in their condition as sediment, was sufficient 

 for their mineralisation ; on the other hand, as the minerals 

 composing the members of the second group are chiefly hydrous, 

 it is contended that their methylosis has been effected by 

 additional water penetrating them, and flowing from Hrtraneous 

 or foreign sources. Compared with each other, mineralised 

 rocks may be classed as xerothermal, and methylosed as hydro- 

 thermal. 



Various evidences are adduced to show that (L) borne 

 ophites have been originally igneous, and others sedimentary 

 rocks " — a conclusion favouring their secondary, and consequently 

 their methylotic origin. 



(M.) " Some crystalline limestones are simply mineralised, 

 such as carrarite ; though rocks closely related to them — viz., 

 " Dolomites have undergone methylosis." With regard to the 

 latter, however, the authors do not accept von Buch's theory of 

 dolomitisation in its general application. Admitting various 

 kinds of this phenomenon, they conceive the change in certain 

 well-known cases has been effected by the action of the soagnesian 

 constituents of sea-water on subjacent beds of limestone ; for 

 example, during the closing portion of the Triassic period, as 

 strongly supported by geologicrl evidences, determined by Ram- 

 say and others, the seas in certain European regions became dried 

 up or reduced; and their water, Laded with magnesian salts, 

 sank through the subjacent sandstones and marls into the Permian 

 limestones, thus converting them into dolomites. Irish corro- 

 borative cases are mentioned. The dolomites of the Tyrol are 

 held to have originated in the same way ; but it is admitted to 

 be probable that the predazzite of the Canzacola Mountain, Val 

 di Fassa, was dolomite that became hydrated by the heated 

 wazer which accompmied the eruptio.i of the immediately adja- 

 cent and overlying monzonite. "Serpentinisation effected in 

 deposits without the intervention of mineralisation" is admitted 

 in the production of the magn;so-argillite at Vallecas, near 

 Madrid, also of that in the Paris Basin, and other localities ; for 

 Sullivan and O'Reilly have shown that it was originally a non- 

 majnesian deposit. 



The authors conclude by treating of (N) "The cbrono- 

 geological range of ophites, &c, and the age of their methylosi-." 

 Offering merely possible suggestions as to the age in which this 

 phenomenon took place in what may be regarded as the oldest 

 ophites (as the subject is beset with considerable difficulties), 

 instances referable to secondary periods, as the dolomites and 

 serpentine rocks of the Tyrol, &c, are briefly noticed ; but they 

 refer more confidently to the methylosed enphotides, &c, of 

 Northern and Central Italy, which, having burst through cre- 

 taceous limestone (alberese), eocene sandstones and schists, have 

 incontestably produced gabbro verde during late tertiary ages. 

 Moreover, it would appear from the discoveries of Achiardi, 

 that argillaceous schists, in Tuscany, are now being serpentinised 

 by the action of magnesiated water. And, taking the wide range 

 of evidences which have been adduced into consideration, it can 

 scarcely be doubted that the same process is still in operation in 

 deep-seated rocks, permeated by heated waters. 



of the mica group, by C. Rammelsberg. — Modulus of elasticity 

 of ice, by L. Reusch. — The cross-pendulum, an apparatus for 

 graphic representation of curves of vibration, by P. Schbnemann. 

 Gegenbaur' s Morphologisches jlahrbuch, vol. vi. part I, 1880. — 

 A. Rauber, continuation of first section of his treatise on trans- 

 formations and their causes in the development of vertebrata 

 (pp. 1-48). — G. Born, postscript to former papers on the carpus 

 and tar-us in amphibia and reptiles, plate I (pp. 49-78). — W. 

 Geisbrechf, histology of teeth in echinoids, plate; 2-5 (pp. 79- 

 105). — Leo Gerlach, a case of tail-formation in a human embryo, 

 with careful histological drawings, showing an indubitable noto- 

 chorrl, plate 6 (pp. 106 124). — M. von Davidoff, on the skeleton 

 of the hind-limbs of hobstean ganoids and physostomous 

 teLosteans. 



The Bulletin de V Acadlmie Royale des Sciences de Belgique, 

 No. 12, 1S79. — On the variations of the specific heat of carbonic 

 acid at high temperatures, by M. Valerius. — Red spot observed 

 on the planet Jupiter during the oppositions of 1878 and 1879, 

 by M. Niesten. — Denominations given to the spots of the planet 

 Mars, by M. Terby. — Method for determining all the ordinary 

 singularities of a locus defined by k algebraic equations contain- 

 ing k — I arbitrary parameters, by M. Saltel. — The classification 

 of birds since Linnaeus, by M. de Selys Longchamps. — The 

 development of the vegetable kingdom in geological times, by 

 M. Gilkinet. — Jury report on the sixth period of quinquennial 

 competition in the mathematical and physical sciences. 



No. I, 1SS0. — Existence of a double apparatus and of two 

 sanguineous liquids in Arthropoda, by M. van Bentden (sealed 

 packet). — Remarks on the existence of evolution in curves of 

 the third order and fourth class, by Prof. Weyr.— Description 

 of an isochronous elliptic governor, the speed of whose action 

 can be varied at will, by M. van Rysselberghe. 



Archives des Sciences physiques el naturelies, February 15. — 

 Swiss geological review for 1S79, by M. E. Favre. — On the 

 time required for surveys of the heavens made with different 

 magnifying powers of the telescope, by M. Thury. — On the con- 

 stitution of napbtaline and of its derivatives, by MM. Revcrdin 

 and Nolting. — Directive ideas for the history of the vegetable 

 kingdom since the tertiary epoch, by Dr. Engler. — Variations of 

 the magnetic declination deduced from regular observations at 

 Moncalievi, in the peri jd 1870-71, by Pere Denza — A series of 

 researches on the pelagic fauna of the lakes of Te.-sin and of 

 Italy, by Dr. Favesi. 



Reale Islituto Lombardo di Scienzft Lettere, Rendicon'i, vol. 

 xiii. fasc. i. — The mat ncro and the phylloxera at Valmodiera, 

 by S. Trevisan. — Congenital syphilis by direct paternal influ- 

 ence, 4c, by Prof. Scarenzio. — On new facts proving the ability 

 of ascarides to perforate unaltered membianes within the 

 abdomen, by Prof. Sangalli. — Contribution to the histology of 

 the voluntary muscles, by Prof. Golgi. 



Cosmos, February. — Prof. Dr. Fritz Schultze, on the history 

 of the origin of the conception of soul.— Dr. C. Forsyth Major, 

 on quaternary horses (translated from Archivio per /'Antro/o- 

 logia, 1879), A. W. Buckland. 



The Atti della R. Accademia dci Lined, January. — On the 

 chemical composition of the soil of the serpentine of Tuscany, 

 by S. Cossa. — On the craniun of a crocodile discovered in the 

 eocene strata of Veronese, by Baron de Zigno. — Revindication 

 on some correlations between the thermal and other physical 

 properties of bodies, by S. Cantoni. 



The Revue Internationale des Sciences biologiques, February.— 

 M. Vulpian, physiological study of poisons, No. 3. — On jaborancli 

 (conclusion). — M. Debierre, on the origin and the evolution of 

 societies, and of the civilisation following contemporary science. 

 Notices of scientific works ; scientific societies ; book notices. 



SCIENTIFIC SERIALS 



Annalen der Physik und Chemie, No. 2. — On the course of 

 formation of resi iual charge in Leyden jars, with constant differ- 

 ence of potential of the coatings, by W. Giese. — On a relation 

 between pressure, temperature, and density of the saturated 

 vapours of water and some other liquids, by A. Winkelmann. — 

 On Newton's dust-rings, by R. Exner. — Remarks on the electro 

 dynamic fundamental laws of Clausius, Riemann, and Weber, 

 by J. Frbhlich.— General theory of the damping exercised by a 

 multiplier on a magnet, by K. Schering. — Chemical monography 



SOCIETIES AND ACADEMIES 

 London 

 Linnean Society, March 18.— Prof. Allman, F.R.S., pre- 

 sident, in the chair.— The President said that before entering on 

 the ordinary business of the meeting it became his melancholy 

 duty to announce the death of Prof. Thos. Bell at the age of eighty- 

 seven Prof. Hell was the oldest Fellow of the Society, having 

 been elected into it in the year 1815. He had held the presiden- 

 tial chair for many years, and under his judicious and able 

 guidance the Society had marvellously advanced in prosperity. 



