OTHER LEUCITE LOCALITIES. 171 



Derby found it,* in 1887, in leucitite from the vicinity of Rio Janeiro, 

 Brazil. For the leucite from Choi, Persia, described by Steinecke in 1887, 

 see the reference above under Pohlig. In 1887 J. W. Judd f announced 

 the discovery of leucite at Byrock mountain, in New South Wales, by 

 T. W. Edgeworth David, who with W. Anderson described it in full in 

 1889. A boulder of leucite rock from Ishawooa canyon, Absaroka range, 

 Wyoming, was described by Arnold Hague J in 1889, since which date the 

 rocks have been discovered in place and have been treated at length by 

 J. P. Iddings under the name of leucite-absarokite. § In 1889, also, J. 

 Shearson Hyland|| detected leucite in a leucite-basanite from the vol- 

 cano of Kiiima-Xjaro in Africa, making the first announcement of it 

 from the African mainland. In 1890 A. Lacroix ![ made known its oc- 

 currenceat Trebizond, Asia Minor, and in the same year v. Chrustschoff** 

 announced a new occurrence on the banks of the Tunguska river, in 

 Siberia. In 1892, from some newly discovered material presented by 

 J. F. Kemp to 0. A. Derb) r , Hussakft described a leucite-tephrite from 

 New Jersey, although onty alteration products were present in the speci- 

 men. The locality was later described in detail by Kemp, XX wno m time 

 identified actual leucite. Backstrom §§ reported leucite in 1896 from the 

 Lipari islands. The greatest interest in connection with this present 

 paper attaches to the work of Weed and Pirsson in^the outlying ranges 

 of the Rocky mountains in Montana. Leucite rocks have been met by 

 them in the Bearpaw mountains, | | and a very peculiar leucitic, plutonic 

 rock called missourite has been described by them from the Highwood 

 mountains.*!*! Dr Hoffmann, of the Canadian Geological Survey, as cited 

 by Weed and Pirsson, has reported leucite in boulders from the Horse- 



* Quarterly Journal of the Geological Societ3 r . August, 1887, p. 463. The determinations were 

 made b}- Rosenbuseh. Compare also O. A. Derby, idem, May, 1891, p. 261, and F. von Graeff, 

 Neues Jahrbuch, vol. ii, 1887, 258, and F. Hussak, Idem, vol. i, 1890, p. 160, regarding pseudo- 

 leucites. 



t Mineralogical Magazine, vol. vii, 1887, p. 190. Also T. W. Edgeworth David and W. Anderson, 

 "The L,eucite basalts of New South Wales," Records of the Geological Survey of New South Wales, 

 vol. i, pt. 3, p. 153, Sydney, 1890. 



j Am. Jour. Sci., vol. xxxviii, 1889, p. 47. 



§ Journal of Geology, vol. iii, 1895, p. 938. 



|| Tschermaks Mittheilungen, vol. x, 1889, p. 261. 



fiComptes Rendus, vol. ex, 1890, p. 302. More fully desctibed in the Bulletin de la Societe geo- 

 logique de France, (3), vol. xix, 1891, p. 737. M. I,acroix also announced probable leucite from 

 Mont Dore, in France, in 1891, but the identification in not absolute, Comptes Rendus, vol. cxiii, 

 1891, p. 751. 



** Bull. Imp. Acad, of Sciences, Saint Petersburg, vol. xxxiv, 1891, p. 225. Also in Neues Jahr- 

 buch, vol. ii, 1891, p. 224. 



it Neues Jahrbuch, vol. ii, 1892, p. 153. 



XX Am. Jour. Sci., April, 1893, p. 298 ; May, 1894, p. 339. 



$1 Geol. Foren. i Stockholm, Forhandl., vol. xviii, p. 155. 



|| Am. Jour. Sci., August, 1896, p. 143 ; Sept., 1896, p. 194. The latter reference refers to pseudo- 

 leucites. 



^Ara. Jour. Sci., Nov., 1896, p. 315. 



