knowlton.1 TERTIARY PLANTS OF NORTH AMERICA. 223 
Sphenopteris Mantelli Brongn.=Onychiopsis Mantelli. 
Sphenopteris membranacea Lx. =Dryopteris arguta. 
Sphenopteris nigricans Lx. Ann. Eept. U. S. Geol. and Geogr. Surv. 
Terr., p. 394, 1873 [1874] ; Tert. Fl., p. 51, pi. ii, f. 4-5«, 1878. 
Denver group: Golden, Colorado. 
Laramie group : Black Buttes, Wyoming. 
Sphenopteris pachyphylla Font. Potomac Fl., p. 93, pi. 1, f. 5, 1889. 
Potomac formation : Trents Reach, Virginia. 
Sphenopteris spatulata Font. Potomac Fl., p. 93, pi. 1, f. 4, 1889. 
Potomac formation : Trents Keach, Virginia. 
Sphenopteris thyrsopteroides Font. Potomac Fl., p. 89, pi. xxv, f. 
3; lviii, f. 5, 1889. 
Potomac formation: Fredericksburg and near Dutch Gap Canal, 
Virginia. 
Sphenopteris valdensis? Heer. Fl. Foss. d. Portugal, p. 14, 1881; 
Font., Proc. U. S. Nat. Mus., vol. xvi, p. 263, pi. xxxvi, f. 2, 1893. 
Trinity division : Glenrose, Texas. 
SPHENOZAMITES Brongniart. Tableau Veg. Foss., p. Gl [110], 
1849. 
Sphenozamites sp., Dn. Trans. Roy. Soc. Canada, vol. iii, sec. iv, p. 
7, 1885 [1886J. 
Kootanie: Martin Creek, British Columbia. 
Spheria lapidea Lx.=Rossellinites lapideus. 
Spheria myrica3 Lx. = Spha?rites myrica3. 
Spheria rhytismoides Lx. = Spha3rites Lesquereuxi. 
SPIR-ffiA Linnaeus. Syst. Nat., ed. i, 1735. 
Spiraea Andersoni Heer. Fl. Foss. Alask., p. 39, pi. viii, f. 3, 1869. 
Eocene^: Port Graham, Alaska. 
SPIRAXIS Newberry. Ann. N. Y. Acad. Sci., vol. iii, p. 219, 1885. 
Spiraxis bivalvis Ward. Bull. U. S. Geol. Surv., no. 37, p. 14, pi. i, 
f. 3,1887. 
Fort Union group : Clear Creek, Montana. 
STAPHYLEA Linnaeus. Sp. PI., ed. i, p. 270, 1753. 
Staphylea acuminata Lx. Ann. Kept. U. S. Geol. and Geogr. Surv. 
Terr., p. 415, 1873 [1874]; Tert. Fl., p. 267, pi. xlviii, f. 4, 5, 1878. 
Green River group: Middle Park, Costellos Ranch, and Florissant, 
Colorado. 
STENOPTERIS Saporta. Palcont. Francaise: PI. Jur., vol. i, p. 
290, 1870. 
Stenopteris virginica Font. Potomac Fl., p. 112, pi. xxi, f. 8, 1889. 
Potomac formation: Near Brooke, Virginia. 
STERCULIA Linnaeus. Diss. Dass., p. 29, 1747. 
Sterculia aperta Lx. Cret. and Tert. Fl., p. 82, pi. x, f. 2, 3, 1883; Fl. 
Dak. Gr , p. 185, pi. xxii, f. 4, 1892. 
Dakota group : Kansas. 
