MINERALOGY. 701) 



Tetrady.mite. Couipositiou iliscussed, F. A. Genth, Am. Phil. 800. Philad., Oct. 2. 

 Tetrahedrite. Crystals from Colorado, Liweh, Zs. Kr., x, 488. 



Lake City, Colo., analyses, Gunth, Am. Phil. See. Philad., Oct. 2. 

 TiEMAJJNiTE. From Utah, iu tetraliedral cry.stala (like sphalerite), also analysis, S. L. 



Penlield, Am. J. 8c., xxix, 419. 

 Tin, NATIVE. From New South Wales, with platinum, etc., F. A. Genth, Am. Phil. 



Soc. Philad., Oct. 2. 

 TiTANiTE. From Lewis County, New York, ai>pan'ut cleavage due to twinning, G. 

 H. Williams, x\m. J. Sc!, xxix, 486. 

 Occui-rence (and analysis) with other minerals iu the District of Columbia, G. P. 



Merrill, Proc. U. S. Nat. Mus., 351, I8d."). 

 Lehigh County, Pennsylvania, analysis, Knerr and E. F. Smith, Am. Ch. J., vi, 



412. 

 Statesville, N.C., analysis, Genth, Am. Phil. Soc. Philad., Oct. 2. 

 Topaz. Crystal from Alabaschka iu the Ural, Griiuhut, Zs. Kr.,x, 263. 



Discussion of paper by Griiuhut (Zs. Kr.,ix, 113), with additional lists of angles, 



V. Kokscharow, Min. Russlands, ix, 97. 

 Urals, crystals with vicinal plaues, etc., F. J. Wiik, Oefv. Fiusk. Vet. Soc, xxvii. 

 Pyro-electricity, Friedel and Curie, Bull. Soc. Min., viii, 16. 



Stoneham, Me., examination, also of alteration products, F. W. Clarke and J. S. 

 Diller, Am. J. Sc, xxix, 373; analysis, Genth, Am. Phil. Soc. Philad., Oct. 2. 

 Tourmaline. Investigation of Pyro-electricity, Riecke, Nachr. k. Ges. Wiss. Gottin- 



gen, Dec. 30, p. 405. 

 Tridymite. Crystals from Krakatau, G. vom Rath, Zs. Kr., x, 174. 

 Turquois. General description, von Kokscharow, Min. Russlands, ix, 83. 



Pseudomorph after apatite, G. E. Moore and V. von Zepharovich, Zs. Kr., x, 240. 



Uintahite. a variety of asphaltum from the Uintah Mountains, Utah, W. P. Blake, 



Eng. & Mining J., Dec. 26. 

 Uraninite. Found in Black Hills, Dakota, L. W. Stillwell, Am. J. Sc, xxx, 82. 



Vanadinite. Crystals from New Mexico, analyzed and described, F. A. Genth and G. 



vom Rath, Zs. Kr., x, 460 ; Am. Phil. Soc. Phila., April 17. 

 Wanlockhead, Scotland, Analysis, Genth, Am. Phil. Soc, Phila., Oct. 2. 

 Vesu VIANITE. Discussion of measurements by himself, Zepharovich, and others, witii 



lists of calculated angles, N. Kokscharow, Miss Russlands, ix, 150. 



Wad. From Wester Silfberg, Sweden, analysis, Weibull, Min. petr. Mitth., vii. 



Xenotime. Crystals from El Paso County, Colorado, W. E. Hidden, Am. J. Sc, xxix, 

 249. 



Zkolites. Discussion of the optical properties, i)yroguostics, &c., of the various 

 species of the group with a view to developing the methods of distinguishing 

 between them, Lacroix, Bull. Soc. Minn., viii, 321. 



Zircon. Crystal with iP from Burgess, Canada, W. E. Hidden, Am. J. Sc. xxix, 250. 

 Chemical examination, Liunemanu, Ch. News, liii, 220,233,240. 



explanations of abbreviations employed. 



Am. Ch. J. — American Chemical Journal, Baltimore. 

 Ann. Ch. Phys. — Annales de Cbimio et do Physique, Paris. 

 Am. J. Sc. — American Journal of Science, New Haven. 

 Ann. Min. — Annales des Mines, Paris. 



Am. Phil. Soc. Philad. — American Philosophical Society of Philadelphia. Proceedings. 

 Ber. Ak. Berlin. — Sitzungsberichte der kais. preuss. Akadomie der Wjssenschafteu, 

 Perlip. 



