WEEKS.] 
PETROLOGY, AND MINERALOGY FOR 1892-1900. 
313 
Petrology— Continued. 
List of rocks described— Continued. 
Sandstone, Day, 1465. 
Sandstone, Diller, 1507. 
Sandstone, Hopkins, 2736. 
Sandstone, Kemp, 2993. 
Saussuritic rock, Ferrier, 1813. 
Saxonite, Diller, 1507. 
Saxonite, Merrill, G. P., 3951. 
Scapolite, Spurr, 5181. 
Scapolite rock, Smyth, 5076. 
Sehefferite, Wolff, 6418. 
Schist, Barlow, 244. 
Schist, Becker, 345. 
Schist, Collie, 1053. 
Schist, Cross, 1184, 1190. 
Schist, Cushing, 1241. 
Schist, Dale, 1254. 
Schist, Keith, 2958. 
Schist, Kemp, 2986, 2987, 2993. 
S'hist, Lewis, 3508. 
Schist, Luquerand Ries, 3598. 
Schist, Van Hise and Bayley, 56%, 5701. 
Schist, andalusite and staurolitic, Hoffman, 
2657. 
Scoria, Diller, 1504. 
Sericitc schist, Clements, 1014. 
Sericite schist, Hoffman, 2657. 
Sericite-schist, Winchell and Grant, 6376. 
Sericitic chlorite schist, Williams, 6159. 
Serpentine, Clements, 1014. 
Serpentine, Diller. L507, 1508. 
Serpentine. Fairbanks, I75:s. 
Serpentine, Hall, 2251. 
Serpentine, Kemp, 2993. 
Serpentine. I.auson. 3416. 
Serpentine. Lew is, 3508. 
Serpentine, Lindgren, 3531. 
Serpentine. Merrill. 3937. 
Serpentine, Rand, 4526. 
Serpentine, Ransome, 1533, 4543. 
Serpentine, Smyth, C. H., jr., 5082. 
Serpentine, Turner. 5465, 5172. 
Serpentine, Winchell and Grant, 6376. 
Shale, Diller, 1507. 
Shonkinite, Pirsson, 1408. 
Shonkinite, Weed. 5946, 5946. 
Shonkinite, Weed and Pirsson, 6927, 6929,5936. 
Shoshonite, Iddings, 2832, 2847. 
Siderite, Winchell and Grant, 6376. 
Silicoferrolyte, Winchell, 6277. 
Sinter, Diller. 1507. 
Slate. Adams, 14. 
Slate, Collie, 1053. 
Slate, Diller, 1507. 
Slate, Duden, 1554. 
Slate, Kemp, 2993. 
Slate, Van Hise and Bayley, 5696. 
Soapstone, Kemp, 2993. 
Soda-granite, Matthew, W. D., 3798. 
Soda-granite, Turner, 5479. 
Soda-granite, Turner and Ransome, 5470. 
Soda-microline, Weidman, 5970. 
Soda-rhyolite, Palache, 4239. 
Soda syenite, Turner, 5480. 
Sodalite-syenite, Lindgren, 3515. 
Solvsbergite, Washington, 5875. 
Petrology— Continued. 
List 0/ rocks described— Continued. 
Spherulite rock, Smith, 5025. 
Stalactite, Diller, 1507. 
Staurolitic mica-schist, Diller, 1507. 
Staurolitic mica schist, Grimsley, 2185. 
Steatite, Diller, 1507. 
Syenite, Becker, 345. 
Syenite, Cross, 1187, 1191 
Syenite, Cushing, 1246. 
Syenite, Diller, 1507. 
Syenite, Ferrier, 1813. 
Syenite, Kemp, 2993. 
Syenite. Keyes, 3108. 
Syenite, Pirsson, 4408. 
Syenite, Selwyn, 4908. 
Syenite, Smyth, 5095. 
Syenite, Turner, 5466. 
Syenite, Turner and Ransome, 5485. 
Syenite, Washington, 5879. 
Syenite. Weed. 5946. 
Syenite, Weed and Pirsson, 5929, 5942. 
Syenite (quartz syenite porphyry), Weed and 
Pirsson, 5935. 
Syenite. Winchell and Grant, 6376. 
Syenite-gneiss, (iordon, 2066. 
Syenite-porphyry, Cushing, L244. 
Syenite-porphyry, Weedand Pirsson, 5942. 
Taconite, Winchell and Grant, 6376. 
Talc, Smyth, 5087, 5088. 
Talc-schist, Turner, 5465. 
Teschenite, Gregory, 2166. 
Theralite, Diller, 1507. 
Theralite, Weed, 6946. 
Theralite. Wolff, 6407. 
Thomsonite, Winchell. 6346. 
Tinguaite, Washington, 5s72, 5875. 
Tinguaite (quartz tinguaite porphyry), Pirs- 
son, 1390. 
Tinguaite (pseudo-leucite sodalite tinguaite), 
Pirsson, 1390. 
Tinguaite-porphyry, Weed and Pirsson, 5942. 
Tonalite, Emerson, h',77. 
Tourmaline-schist, Patton, 4260. 
Trachyte, Bergeat, 123. 
Trachyte, Cross, 1187, 1191. 
Trachyte. Diller, 1507. 
Trachyte. Gregory, 2166. 
Trachyte, Kemp, 2993. 
Trachyte, Lindgren, 3515. 
Trachyte, Ordonez, 4141, 4142. 
Trachyte, Todd, 5407. 
Trachyte. Weedand Pirsson, 5936. 
Trachyte-porphyry, Weed, 5946. 
Trachyte-rhyolite, Iddings, 2846. 
Travertine, Berkey, 425. 
Travertine, Diller, 1507. 
Troctolyte, Elftman, 1634. 
Troctolyte, Winchell, 6277. 
Tuff, Bascom, 276. 
Tuff, Berkey, 428. 
Tuff, Cross, 1190. 
Tuff, Emerson, 1674. 
Tuff, Emmons, Cross, and Eldridge, 1707. 
Tuff, Ferrier, 1813. 
Tuff, Iddings, 2823. 
Tuff, Lawson, 3416. 
