468 KECORD OF SCIENCE FOR 1886. 



Phenacite. Floiissant, Colorado, crystals described, A. Des Cloizeaux, Am. J. Sc, 

 XXXII, 210; Bull. Soc. Miu.,ix, 171. 

 From the Alps, Seligmaun, Ber. nied. Ges. Bonn, May 11, 1835, Oct. 3, 1886. 

 Phillipsite. Crystallograpliic and chemical relations discussed, Langemann, Jb. 



Min., II, 110. 

 Phosgenite. Sardinia, occurrence at Monteponi, Lovisato, Att. Accad. Line. [4], ii, 



254. 

 Finite. ^S'ee Agalmatolite. 



Planerite. Ural, optical characters, Lacroix, Bull. Soc. Min., ix, 5. 

 Plattnerite. Leadhills, analysis (PbOj), and shown to be a good species, E. Kiuch, 



Min. Mag., vii, 63. 

 POLYARSEXITE. Relation to hematostibiite, Igelstrom, Geol. For. Forh., viii, 179. 

 PsEUDOBROOKiTE. Mout Dore, crystals described, Oebbeke, Zs. Kr., xi, 370. 

 Ptilolite. Jefi'erson County, Colorado, a new zeolite, W. Cross and L. G. Eakins, 



Am. J. Sc, xxxii, 117. 

 Pyrargyrite. Audreasberg, twin crystals with hemimorphic development, and dis- 

 cussion of twinning in general, Schuster, Zs, Kr., xii, 117 ; Verb, G. Reichs., 70. 

 Pyrite. Brosso, Piedmont, crystals described, Bruguatelli, Att. Accad. Torino, 1885, 

 20. 

 Baltimore County, Maryland, complex crystal (changed to limonite) described, 



G. H. Williams, Johns Hopkins Univ. Circular, Lii. 

 California, crystals described, A. W. Jackson, Proc. Cal. Acad. Sc, No. 4, 365, 370. 

 Pyrochroite. Nordmark, Sweden, crystals described, G. Fliuk, Bihang Vet. Akad. 



Handl., xii, 2, 12. 

 Pyrostilpnite. Chemical examination, Streng, Jb. Min., i, 57, 



Pyroxexe. Nordmark, Sweden, crystallographic monograph, G. Flink, Zs. Kr., xi, 

 449. 

 A^ar. diopside from Val d' Ala, crystallographic monograph, G. La Valle, Accad. 

 Line, Mem. [4], iii, June 6. 

 Ala and Reichenstein, description of crystals with summary of all planes ob- 

 served, with authoiities, etc., Gotz, Zs. Kr., xi, 236. 

 Crystals from De Kalb, New York, described, vom Rath, Ber. iiicd. Ges. Bonn, 

 July 7. 

 Kremnitz, Hungary, crystals of grass-green color described, A. Schmidt, Zs. Kr., 



xii, 100, 

 Twin crystals in quartz trachyte, A. D'Achiardi, Att. Soc. Tosc, vii, 40. 

 Tyrol, crystals described with analysis, v. Zepharovich, Lotos, 1885. 

 Twinning structure developed by pressure, Miigge, Jb. Min., i, 185. 

 Var. augite, Dognacska, analysis, Loczka, Zs. Kr., xi, 262. 

 Pyrriioarsenite. Grythyttan, Sweden, new mineral described, Igelstrom, Bull. 



Soc. Min., IX, 218, 

 Pykuiiotite. Cyclopean Islands, crystals described, Seligmann, Zs. Kr., xi, 343. 

 Artificial formation, with discussion of chemical composition, Doelter, Min. petr. 

 Mitth., VII, 535. 

 Quartz. Alexander County, North Carolina, description of crystals, vom Rath, Yer^ 

 Nat. Cassel, Festschrift. Crystals with the basal plane, W. E. Hidden and A. Des 

 Cloizeaux, Am. J.Sc, xxxii, 208. 

 Impression-forms resembling pseudomorphs, W. E. Hidden, School of Mines 



Quart., VII, 334. 

 Is. Giglio, crystals described, Busatti, Att. Soc. Tosc, vii, 196. 

 Determination of the constants of elasticity for rock crystal, Voigt, Festschrifr, 



Gcittingen. 

 Decoloration of agate exposed to the sun's rays, Dutremblay du May, Bull. Soc, 



Min., IX, 216. 

 St-C16ment, pleromorphs, Gonnard, C. R., cm, 1036. 



