Notices respecting New Books. 149 



The Mode of Formation of the Granitic Effusions of Neudeck and 

 Carlsbad, and the History of the Stanniferous Rock-formation in 

 the Erzgebirge. A Study by Ed. Reyer. (Tektonik der Graniter- 

 giisse von Neudeck und Karlsbad, und Greschichte des Zinnberg- 

 baues im Erzgebirge. Studie von Ed. Reyer.) Reprint from the 

 4 Jahrbuch d. k.-k. geol. Reichsanstalt/ vol. xxix. pt. 3, pp. 405 

 et seq. Vienna, 1879. 



This memoir divides itself into : — 1. A study of the relations of 

 the granite and schists ; 2. A discrimination of the various local 

 kinds of granite, as being necessary for a knowledge of the nature 

 and origin of the granitic masses — -with both earlier descriptions of 

 the several granites and the author's own researches ; 3. The his- 

 tory of the most important tin-bearing rocks and tin-works of the 

 district. These chapters are illustrated with several woodcuts, 

 among which is a plan of the country between Carlsbad, Ebenstock, 

 and Schwarzenberg. The literature relating to the subjects above 

 mentioned is fully indicated in each division. 



As to the origin and subsequent conditions of such granite- 

 systems as these of North-western Bohemia, the author considers 

 that, in deep water, the erupted rock-material issued from a series 

 of parallel fissures, and generally became crystalline on account of 

 the pressure. These eruptive masses formed themselves into one 

 great whole. The fissures were enlarged, and gave out more and 

 more eruptions, which formed broadly obtuse cones ; and these have 

 their main axis coincident with the strike of the fissures. Fine- 

 grained mud-like laminae also were intercalated on the sides of the 

 cones among the erupted matter. Here and there the consolidated 

 crust burst, and the still liquid rock below was injected into the 

 new fissures, thus giving " rise to apophyses, which vary in appear- 

 ance from fine-grained rock below to veins of segregation above. 

 Ultimately the whole was covered with tuff and deep-sea mud. 



The massif thus formed, having become dry land in course of 

 time, was subjected to erosion. The soft shaly coating was gra- 

 dually removed; and the upper crust of the ejected rock-mass was 

 then worn away, until the cone-like injections appeared. Lastly 

 the granitic mass, having been furrowed throughout, was finally 

 removed, leaving a system of granite veins, more or less linear and 

 concentric, in the old schists. 



On the Structure of the Volcanos of Bohemia. By Ed. Reyer. 



(Ueber die Tektonik der Vulcane von Bohmen, &c.) Reprint 



from the ' Jahrbuch d. k.-k. geol. Reichsanstalt,' vol. xxix. pt. 3, 



pp. 464 et seq. Yienna, 1879. 



The relation of the North-Bohemian series of volcanos to the 

 Erzgebirge is indicated; and then the concentric, onion-like, and 

 bulbous arrangement of the phonolitic material in the Schlossberg 

 of Teplitz, previously noticed by Reuss, is dwelt upon. The vol- 

 cano of Priesen is especially described and illustrated, as belonging 



