352 T. W. E. DAVID, F. B. GUTHRIE, AND W. G. WOOLNOUGH. 



Dr. F. Adams 1 and Mr. A. P. Coleman 2 have described a corun. 

 diferous nepheline syenite from Eastern Ontario. This remarkable 

 rock is described as having a schistose structure, " so that at first 

 sight it would be called gneiss. The darker layers contain much 

 biotite and the lighter nepheline and plagioclase. Numbers of 

 small crystals of corundum stand out on the weathered surfaces. 

 Mr. Frank D. Adams has referred 3 to a rock formed of white 

 felspar and orange-red grains of eleeolite, described by Sir William 

 Logan from Old Pic Point and Island, Lake Superior. It is 

 thought to be probably related to the remarkable analcite rock 

 called heronite, described by A. P. Coleman from Heron Bay, 

 Lake Superior. 4 This rock, heronite, is considered to have the 

 following mineral constitution : — 



Analcite ... 



47-00 



Orthoclase 



28-24 



Labradorite 



1300 



^Egyrite ... 



4-04 



Limonite ... 



3-59 



Calcite 



1-96 



97-83 



As regards the occurrence of nepheline rocks in the Southern 

 Hemisphere, phonolites containing sanidine, nepheline, haiiyne 

 and hornblende, have been described from Fernando Noronha, off 

 Cape S. Roche, Brazil; 5 and Renard 6 has described a volcanic 



1 Geol. Sur. Canada, 1892-3, Pt. J, p. 5; and also Amer. Journ. Sci., 

 Vol. xlviii., July 1894, pp. 10 - 18. 



2 Jour, of Geol., July - August 1899, Vol. vn., No. 5, pp. 437 - 444. 



3 Jour, of Geol., Vol. vin., No. 4, May - June 1900, pp. 322 - 325, " On 

 the probable occurrence of a large area of nepheline-bearing rocks on the 

 north.east coast of Lake Superior. 



4 Jour, of Geology, Vol. vn., No. 5, July - August, 1899, p. 435. 



5 Gumbel, Phonolith von Fernando do Noronha, Brazilien, Min u. petr. 

 Mitth. ii., 1880, 188. Renard, Rep. on the petrology of Oceanic Islands, 

 1889, 33. Branner and Williams, Amer. Journ. of Sci., xxxvn., 1889, 

 145, 168. 



6 Renard, Phonolithe de F isle Nightingale (Tristan da Cunha), Bull. 

 Acad. Royale de Belg. (3) xiii., 1887, 3. Eenard, Report on the petrology 

 of oceanic islands, 1889, 89. 



