214 PETEOIOGT. 



constituents — quartz, muscovite, biotite, a green mica, clastic particles, 

 garnet, an unknown yellow mineral, and iron-ore ; 2. Structure and 

 varieties — granular, schistose, and spotted (JlecJcig) ; 3. Its enclosures : 

 the results of microscopic examination show that the rock is an " altered 

 grauwacke," and is improperly called a mica-trap. F. W. E,. 



Kalkowsky, Dr. Ernst. Rother Gneiss und Kalkstein im Wilischthal 

 im Erzgebirge. [Red Gneiss and Limestone in the Wilischthal.] 

 Zeitsch. dcutsch. geol. Oes. Heft iii. pp. 623-630 ; woodcut. 



The " red gneiss " of the Saxon Erzgebirge has been studied by 

 many geologists, and is generally referred to an eruptive origin. The 

 author describes a geological section showing the gneiss so intimately 

 associated with limestone, that they must have been contemporaneous. 

 But if this limestone is eruptive, then it is argued that all the Archsean 

 series of the Erzgebrige must have had a like origin — a conclusion 

 which cannot be maintained. Hence the alternative that the red gneiss 

 of Saxony is not an eruptive rock. E. W. E. 



Kern, Sergins. Coal in Russia. Chem. Neivs, vol. xxxi. pp. 133, 

 134, and vol. xxxii. pp. 79, 80. 



Part 1. 8 Analyses of Russian Coal, giving in each case the per- 

 centage of carbon, volatile matter, and ash, with calorific power, and in 

 most cases the proportion of sulphur. The coals were from the 

 Goveraments of Nowgorod, of Toula, and of Riasne, the Oural Mts., 

 and the Donetz coal-fields. Part 2. Analyses of 10 samples of coal 

 from the Governments of Toula, Kalouga, Ekaterinoslaw, and Simbirsk, 

 and from the Caucasus and the Donetz coal-fields. E. W. R. 



Kinahan, G. H. Microscopical Structure of Rocks. Report No. 

 1. — Ingenite Rocks. Proc. R. Irish Acad. ser. 2, vol. ii. (Science), 

 part 2, pp. 95-101. No. 2, pp. 161-163, pi. 8. No. 3, 

 pp. 164, 165. No. 4, part 3, pp. 180-182, pis. 7, 8 ; woodcuts. 



No. 1. Premising that the granitic rocks of W. Connau^ht seem 

 capable of being divided into Intrusive Granite (highly siliceous), Non- 

 intrusive Granite (basic), and Elvanyte, the author describes his 

 examination of specimens of the second group, from various places 

 in Galway. The minerals determined in these are orthoclase, adularia, 

 oligoclase, mica, quartz, amphibole, and pyrite. 



No. 2. On the quartz contained in granites from Co. Galway. The 

 appearances under the microscope are described. 



No. 3. Describes the examination of granite from Carnsore Point, 

 Co. Wexford. The mass of the rock is metamorphic ; but in one place 

 some that appeared to be intrusive occurs. It is of a reddish-grey 

 colour, containing krge crystals of pink felspar, together with white 

 felspar, greenish felspar, two micas, quartz, and pyrite. It is some- 

 times distinctly foliated. Eour slices were examined ; and the details 

 are given. The rock seems to belong to the Galway granite type, 

 containing three felspars, orthoclase, adularia ?, and oligoclase. 



