404 



NATURE 



\AugUSt 2 2, 1889 



lain by thick beds of Devonian, Permian, and Carboniferous 

 deposits, and these strata are so folded as to make several parallel 

 chains rising more than 3300 feet above the sea, and containing 

 the highest summits of the region. Further west the country 

 assumes the character of a plateau which is built up of nearly 

 horizontal strata of the formation — st characteristic of the Urals — 

 which has a fauna intermediate between the Permian and Car- 

 boniferous of Western Europe. Above this there are Triassic 

 deposits. 



Several other contributions will be devoted to the same 

 region. One, already published, contains a most elaborate work 

 " On the Lower Devonian Fauna of the Western Slopes of the 

 Urals," by Th. Tchernyshefil'. Until 1880, the bituminous, gray, 

 and dolomitic limestones of the Urals— very poor in fossils as a 

 rule — were thought to be Silurian, but M. Tchernysheff describes 

 107 species recently found in these limestones, and shows that 

 their fauna is of Lower Devonian age. This conclusion is of 

 great importance, as it throws light on the age of the very same 

 series of limestones, quartzites, and slates in Siberia and Turke- 

 stan (also arrayed in ridges running south-west to north-east). 



Another sheet of the geological map covers the most interest- 

 ing region on the right bank of the Lower Volga. 1 Upper Car- 

 boniferous strata appear in that region in the deeper ravines 

 only ; the Cretaceous formation is represented by beds belonging 

 to the Stage Aptieii and Neocomian groups of the Lower Cre- 

 taceous, as also by the Cenomanian, Turonian, and Senonian 

 groups of the Upper Cretaceous. Nearly the whole of the 

 region is covered, however, by Eocene clays and sands; 

 boulders, partly of local origin, and partly carried from North- 

 western Russia, are stre wn over the surface, and the manner of 

 their distribution is such as to exclude thepussibility of transport 

 by floating ice. Prof Sintsofif concludes, therefore, that the ice- 

 sheet of Russia extended as far south-east as the Volga under 

 the 50th degree of latitude. 



Finally, an important contribution to the paleontology of 

 Russia—" The Ammonites of the Aspidoceras acanthicum 

 Beds of East Russia "—is published in the same Memoirs 

 (ij-. 3) by Prof. Pavlow. These beds, which are met with in 

 Simbirsk and ihe Southern Urals, have a mixed fauna, the 

 characters of which may be best explained by the statement 

 that during the Jurassic period Central Asia was under the sea, 

 and that this basin was in connection with the Jurassic basins of 

 both Tibet and Central Europe. 



Besides the above larger works, the Geological Committee has 

 brought out two volumes of Izvestia {Bulletins), which contain 

 a mass of valuable information. Prof. Musliketofif's notes upon 

 the Kalmuck Steppes are, as usual, rich in most suggestive 

 remarks about the activity of wind and water in the desert. He 

 shows also that during the Quaternary period the Caspian Sea 

 did not extend further west than the Ergheni Hills, communicat- 

 ing with the Black Sea through the Manytch Valley only. In 

 a paper on the limits of glaciation in Central Russia and the 

 Urals (vol. iv.), M. Nikitin shows that the ice-sheet extended 

 in Russm as far south as 48° 30' N. latitude on the Dnieper, 

 and 50 on the Volga.^ In a subsequent paper (vol. v.), devoted 

 to the post-glacial deposits of Germany, the same author dis- 

 tinguishes two different kinds of loess, one of which may be due 

 to the agency of wind. Many papers are devoted to the Urals 

 —their crystalline rocks, the traces of glaciation (M. Krotoff, in 

 vol. IV fasc. 9), and the intermediate Permian-Carboniferous 

 beds, the fauna of which, according to Prof. Stuckenberg, con- 

 tains forty-one Carboniferous species, thirty-four Permian, seven 

 species belonging to both, and twenty-three characteristic of the 

 atm"[!'^"i '^™"^ groups. Four papers are devoted by M. 



Mikhalsky to Poland, and it appears that the beds of Poland 

 which were formerly thought to be Jurassic, must be regarded 

 •as Neocomian-that is, Cretaceous. M. Lagusen describes a 

 new sub-genus, LycopJioria, of the Stropkomenidce family : 

 1 rof Schmidt deals with the glacial and post-glacial deposits of 

 the Baltic provinces ; M. Pavlow describes the Exogira virgtda 

 beds, as also some Cretaceous and Tertiary deposits of South- 

 East Russia ; and M. Nikitin gives a sketch of the Carboniferous 

 deposits and the loess of Samara. 



Another work, issued by the Russian Geological Survey, 

 deserves especial mention on account of its general interest and 

 value, Ihis is the annual bibliography of works on geology, 



, \" Carte g^ologiquege'n^rale de la Russie," Feuille 03 ; " Kamyschin " 

 by^I Sintsoff, m Mimoires ciu Comite Geologigue, vol liNo ^ ^ ' 



MitUifungef^ translation of this paper has been published iA Pctermann's 



mineralogy, palaeontology, &c., published in Russia, or works 

 published elsewhere which refer to Russia ("Bibliolheque geo- 

 logique de la Russie "). Brief abstracts, in Russian with a French 

 translation, are given of the more important papers. The titles 

 are given in the original language ; if the original is Russian, 

 then a French version is given ; if the original is not Russian, 

 a translation into this language is added. 



The publications for the year 1885 number 256 ; for 1886, 

 356 ; for 1887, 405 ; and for 1888, 390. But the later series 

 include omissions in earlier numbers. The editor of this useful 

 annual is M. S. Nikitin ; his chief assistant in the work is Mdlle. 

 Marie Tzwetaev. 



SCIENTIFIC SERIALS. 



American Journal of Science, August. — On the observation of 

 sudden phenomena, by S. P. Langley. The paper deals with 

 the apparently inherent defects of human observation, especially 

 in recording unexpected natural phenomena, its object being to 

 reduce this personal error to a minimum. The author believes that 

 a means may be found by which any person, skilled or ignorant, 

 may make not only meridian observations, but an observation of 

 any sudden visible event, of whatsoever nature, so accurately 

 that no correction need be applied. An instrument constructed 

 for the purpose, and here illustrated, has been tried by various 

 observers in various ways, the probable error for any single 

 observation being rather less than one-twentieth of a second.— 

 A spectro-photometric comparison of sources of artificial illumin- 

 ation, by Edward L. Nichols and William S. Franklin. These 

 experiments, rnade in Cornell Univershy during the summer of 

 1888, consist in the spectro-photometric comparison of various 

 artificial sources of light and of daylight with that emitted by a 

 sixteen candle-power incandescent lamp. The sources of light 

 subjected to measurement were a standard candle, various 

 petroleum and illuminating gas flames, a lime-light, two electric 

 arc lights, clear daylight, an incandescent lamp of high resistance 

 at various temperatures, and an incandescent lamp of low resist- 

 ance at normal candle power. The general result is that candle- 

 power as determined by means of the Bunsen photometer aff"ords 

 no correct measure either of light-giving energy or of the lumin- 

 osity of the source of light, the direction of the error always 

 being such as to favour sources of a low degree of incandescence 

 when compared with those of higher temperature. — On the 

 possibility of hemihedrism in the monoclinic crystal system, with 

 especial reference to the hemihedrism of pyroxene, by George 

 H. Williams. A fresh study of the remarkable crystals of 

 pyroxene from Orange County, New York, recently described 

 by the author as hemimorphic, seems to show that they should 

 rather be regarded as hemihedral, and that they are by no means 

 an isolated instance of this pecuHar development in pyroxene. — 

 On the earlier Cretaceous rocks of the north-western portion of 

 the Dominionof Canada, by George M. Dawson. The purpose 

 of this paper is to call attention to certain facts recently brought 

 to light respecting the equivalency of the Queen Charlotte Islands 

 and Kootanie formations, and to the importance of the earlier 

 Cretaceous rocks, of which they are representatives, over great 

 areas of the western and extreme north-western portion of the 

 continent. These facts are just now specially intereting from 

 their analogy to those lately developed by Mr. R. T. Hill 

 respecting a similar earlier Cretaceous formation in the south- 

 western region of the United States.— A new occurrence of 

 gyrohte, by F. W. Clarke. This specimen, from the New 

 Almaden quicksilver mine, California, is shown on analysis, and 

 by comparison with How's figures for a Nova Scotia gyrolite, 

 to be a somewhat impure gyrolite as?ociated with apophyllite, 

 and agreeing approximately with the formula CagSisOg . 3H2O 

 — On action of light on allotropic silver, by M. Carey Lea. The 

 author's further studies of this subject show that light can 

 convert yellow or red-yellow allotropic silver to white, and cause 

 the blue-green modification to pass to the gold-yellow.— Papers 

 were contributed by J. F. Kemp, on certain porphyrite bosses in 

 North-Western New Jersey ; by W. B. Dwight, on recent 

 explorations in the Wappinger Valley limestones and other 

 formations of Dutchess County, New York ; by George F. 

 Becker, on silicic acids ; and by O. C. Marsh, on gigantic horned 

 Dinosauria from the Cretaceous. Mr. Marsh also continues his 

 memoir on the discovery of Cretaceous Mammalia, illustrating 

 the subject with two plates of the teeth of American Creta- 

 ceous mammals. 



