kxxii NOTES. 



accompanied by clay, lime, and potash : Rose, Reise, Bd. ii. S. 187. On the 

 formation of jasper by the action of dioritic porphyry, augite, and hypersthene 

 rock, see Rose, Reise, Bd. ii. S. 169, 187, and 192. Compare also Vol. i. 

 p. 427, containing drawings of the globes of porphyry between which jasper 

 presents itself in the calcareous grauwacke of Bogoslowsk, as produced by the 

 plutonic influence of the augitic rock, Bd. ii. S. 545. Humboldt, Asie cen- 

 trale, T. i. p. 486. 



C* 9 ) p. 249. Rose, Reise nach dem Ural, Bd. i. S. 586588. 



^) p. 249. In respect to the volcanic origin of mica, it is important to 

 notice that crystals of mica are found, in the basalt of the Bohemian Mittel- 

 gebirge, in the lava of Vesuvius of 1822 (Monticelli, Storia del Vesuvio 

 negli anni 1821 e 1822, 99), and in the fragments of argillaceous schist 

 imbedded in scoriaceous basalt on the Hohenfels not far from Gerolstein in 

 the Eifel (see Mitscherlich, in Leonhard, Basalt- Gebilde, S. 244). On the 

 production of feldspar in argillaceous schist by the contact of porphyry 

 between Urval and Poiet (Forez), see Dufrenoy, in Geol. de la France, T. i. p. 

 137. It is probably owing to a similar cause, that certain schists, which I 

 had an opportunity of seeing near Paimpol, in Brittany, during a geological 

 pedestrian excursion with Professor Kunth through that interesting country, 

 derive their amygdaloidal and cellular character (T. i. p. 234, of the same 

 work). 



t 271 ) p. 249. Leopold von Buch, in the Abhandlungen der Akad. der 

 Wissensch. zu Berlin aus dem J. 1842, S. 63 ; and in the Jahrbuchern fur 

 wissenschaftliche Kritik, Jahrg. 1840, S. 196. 



f 72 ) p. 249. Elie de Beaumont, in the Annales des Sciences naturelles, 

 T. xv. pp. 362 372 : " En se rapprochant des masses primitives du Mont 

 Rose et des montagnes situees a 1'ouest de Coni, on voit les couches secondaires 

 perdre de plus en plus les caracteres inherents a leur mode de depot. Souvent 

 alors elles en prennent qui semblent provenir d'une toute autre cause, sans 

 perdre pour cela leur stratification, rappelant par cette disposition la structure 

 physique d'un tison a moitie charbonne dans lequel on peut suivre les traces 

 des fibres ligneuses, bien au-dela des points qui presentent encore les carac- 

 teres naturels du bois." Compare also Annales des Sciences naturelles, 

 T. riv. pp. 118 122, and H. von Dechen, Geognosie, S. 553. We may 

 reckon among the most striking proofs of the transformation of rocks by 

 plutonic action the belemnites in the schists of Nufienen, (in the Alpine 

 valley of Eginen, and near the Gries-glacier), and the belemnites which 

 M. Charpentier found in what was called primitive limestone on the western 



