GEOLOGICAL WKTTTXGS OF GEORGE IT. WILLIAMS. 439 



Progress of the work on tlio Archean goolo<j:y of ^Marvland : /An/., ()5, April, 1S88, 



p. (31. 

 The gabbros and diorite;^ of the " Cortlandt series," on the Hudson river, near 



Peekskill, New York: Am. Joar. Sci., vol. xxxv, June, 1888, pp. 438-448. 

 The contaet-nietaniorphisni produeed in the adjoiniuir nnea-sehists and limestones 



by the massive roeks of the "Cortlandt series," near Peekskill, New York: 



Ibid., vol. xxxvi, October, 1888, pp. 2r)4-2()l), plate vi. 

 Geolo«:y of Fernando de Noronha. Part II. Petrography: Ihid, vdI. xxxvii, 



March, 1889, pp. 178-189. 

 On the ix)ssibility of hemihedrism in the monoelinic crystal system, with esjtecial 



reference to the hemihedrism of pyroxene: Ibid., vol. xxxviii, August, 1889, 



pp. 115-120. 

 Contributions to the mineralogy of Marylaiul : JoJois ]Inpkh)<i ruirtrslli/ ('ircnbirs 



75, 8eptend)er, 1889, p. 98. 

 Some modern aspects of geology : Popuhir Sncncc Moiithh/, September, 1889. 

 Note on the eruptive origin of the Syracuse serpentine: Jiiill. (uol. Soc Aui., vol. 1, 



p. 533. 

 Geological and petrographical observations in southern and western Norway: 



Ibid,, pp. 551-553. 

 Celestite from Mineral county, West Virginia: Am. Jour. Sri., vol. xxxix, March, 



1890, pp. 183-188. 



Same, reprinted in German in Z<i(srJir. Kr>/s(. a. Min., vol. xviii, 1890, p. 1. 



On the hornblende of Saint Lawrence county, New \"ork, and its gliding planes: 



Am. Jour. Sci., vol. xxxix, ^lay, 1890, pp. 352-358. 

 The non-feldspathic intrusive rocks of Maryland and the cour.se of their altera- 

 tion. First paper: The original rocks : .!//<. ^rVo/o/jr<W, vol. vi, July, 1890, p. 35. 

 Elements of crystallography for students of chemistry, physics and mincMalogy: 



New York, H. Holt tS: Co., 8vo, 250 pp., 383 figures and 2 i)lates. 

 The greenstone-schist areas of the Menominee and ^Slanpiette regions in Michigan : 



Ball. Xo. 02, U. S. Geol. Survc}/, Washington, 1890, 241 pp., 29 (igures and UJ 



plates. 

 The silicitied glas.s-breccia of Vermilion river, Sudbury district : />/'//. G'col. Soc. 



Am., vol. 2, p. 138. 

 The petrography and structure of the Piedmont plateau in ^laryland: Ibid., pp. 



301-318. 

 Sixty-eight reviews of American geological and petrographical literature, published 



in the X»'iir.<< JahrbucJi far Minirabxji)', (iiolofjii' a. Pidnonlobxjii', between 1884 



and 1890. 

 Anglesite, ceru.ssite and sulphur from the Mountain View lead mine, near I'nion 



Briilge, Carroll c<junty, Maryland: .A/Az/.s- Hopkins Unircrsifi/ Clrnddrs S7, April, 



1891. [Octavo reprint.] 



.\ natiwe from the Arvon slate quarries, liuckingham county, \'irt:inia: Am. Jnar. 



Sri., vol. xlii, November, 1891, \t. 431. 

 Notes on tiie microscopical character of rocks from the Sudbury mining district, 



Canada. ApjK'ndix I to I>r K. Jiell's paper on the Sudbury minin;^' district : 



Rep. (unl. and Xal. IliM. Sarvry of Onnuht, 188^'<J0, F, pl>. 55-S2. 

 Notes on .some eruptive HM-ks from Alaska. Appendix to Professor II. 1'. Keid'H 



pajicr on the .Muir glacii^r : Xaf. (inuj. .^fatj., vol, iv, |>p. 03-74. 

 I.XIll Mii.i.. fir-oi.. Hoc. Am.. Vol. v,, ihOJ. 



