PETROLOGY. 217 



replaced by two molecules of water. Ten microscopical sections of 

 rocks from the Eonda mountains show their gradual transition to 

 serpentine. J. MeP. 



Malet, H. P. Basalt. Sci. Gos. no. 130, p. 233. 



Mello, Rev. J. M. On the Microscopical Structure of Rocks. Pop, 

 Sci. Rev. vol. xiv. pp. 1-19 ; 2 plates. 



Notes the history of the subject, and refers to its geological bear- 

 ings, describes the characters of various minerals in detail, and con- 

 cludes with notes on the microscopical characters of various sedi- 

 mentary rocks. W. T. 



MdM [Prof.] H. [Minette of the Plauen'sche Grund.] N. Jahrh, 

 Heft ii. pp. 176-179. 



Describes the microscopic structure of sections from the middle of a 

 vein in the Plauen'sche Grund, near Dresden. They show horn- 

 blende, mica, felspar (either orthoclase or plagioclase), magnetite, 

 titanoferrite, an amorphous glass, and apatite. F. W. R. 



. Mikromineralogische Mittheilungen. N. Jahrh. Heft vii. 



pp. 691-724. 

 Notes on the hornblende-andesite of Jakuben, near Tetschen ; on 

 Tschermak's teschenite ; on the olivine-rocks of Ellgoth ; on horn- 

 blende-rock from Karnberg in Saxony ; on the garnet-bearing quartz- 

 diorite of Wolfach in Odenwald ; on the diabase of the Bilstein, and 

 the products of its alteration ; on the augite-porphyry of Ratzcs ; on 

 glassy hauyne-basalt or hauyne-tachylite, and on the felspar-basalts of 

 Otaheite. P. W. R. 



[Eruptive rocks of Ilfeld and Ilmenau.] N. Jahrh. Heft vii. 



pp. 725-729. 



Preliminary notice of the microscopic characters of so-called mela- 

 phyres, minettes, and porphyrites from the neighbourhood of Ilfeld and 

 Ilmenau, where the writer has collected more than 400 specimens for 

 microscopic study. F. W. R. 



Moissenet, Prof. [Analysis of Rock from Pontaven, Finistere.] 



Rev. Geol. t. xii. p. 45. 

 Composition : Quartzose sand 41 ; Fe 1 ; Ca 30*6 ; Mg 0-6 ; 

 loss 26. Total 99-2. 



Moissenet, Prof., and Assistants. [Analyses of Limestones.] Rev. 



Geol. t. xii. pp. 49, 50. 

 The limestones analyzed are from Sainte-Foy-la-Grande, Gironde, 

 and Chalonvillars, near Bclfort-, Doubs. 



Nathorst, A. 0-. Om en gSngformigt upptradande, euritlik bergart. 



[On a vein-forming euritic rock.] Geol. foren. Stockholm Forh. 



Bd. ii. pp. 215-218 ; plate. 

 Occurs, with pegmatite, in yeins through light-red gneiss at Lindholra. 



