Maryland Geological Survey 449 



in arrangement; leaves very small;, narrowly linear, acute or acuminate, 

 widest at base, decurrent, and mostly crowded; midnerve slender but 

 distinct."— Fontaine, 1890. 



Fontaine says of this species : " This plant is a good deal like 8. 

 subidata, but the leaves are proportionately wider and not so falcate, 

 while the ultimate branches are placed at more uniform intervals." It 

 may be doubted whether it is really distinct from the abundant Sequoia 

 Beiclienhachi since it was extremely rare at the single Virginia locality 

 from which it was originally collected and it has not been met with 

 in any of the subsequent collections. It is not especially well marked 

 and is of little significance although it has seemed best to keep it distinct 

 at the present time. 



Occurrence. — Patuxent Formation. Near Dutch Gap. Virginia. 



Collection. — U. S. National Museum. 



Sequoia ambigua Heer 

 Plate LXXVIII, Figs. 1-7 



Sequoia amMgua Heer, 1874, Fl. Foss. Arct., Band iii, Ahth. ii, pp. 78, 91, 



pi. xxi, figs. 1-11; pi. XXV, fig. 5. 

 Sequoia amhigua Heer, 1882, IMd., Band vi, Abth. il, pp. 17, 52, pi. i, fig. 3. 

 Sequoia amhigua Fontaine, 1890, Mon. U. S. G-eol. Surv., vol. xv, 1880, p. 245, 



pi. cxviii, fig. 2; pi. cxx, figs. 1-6; pi. cxxvii, fig. 5; pi. cxxxii, fig. 3. 

 Sequoia amMgua "White, 1890, Am. Journ. Sci., vol. xxxix, p. 97, pi. ii, figs. 



2, 3 

 Sphenolepidium recurvifolium Fontaine, 1890, Mon. U. S. Geol. Surv., vol. 



XV, 1889, p. 258, pi. cxxvii. fig. 2; pi. cxxx, figs. 2, 7. 

 Sphenolepidium dentifolium Fontaine, 1890, Mon. U. S. Geol. Survey, vol. 



XV, 1889, p. 258, pi. cxxviii, figs. 2-6; pi. cxxix, fig. 5; pi. cxxx, figs. 



4-6, 10. 

 Sequoia amMgua Nathorst, 1893, in Felix and Lenk, Beitr. z. Geol. u. 



Palseont. Repub. Mexico, ii Theil, 1 Heft, p. 51, figs. 1-3. 

 Sequoia amMgua Hollick, 1895, Bull. Geol. Soc. Am., vol. vii, p. 13. 

 Sequoia gracilis Fontaine, 1899, in Ward, 19tli Ann. Rept. U. S. Geol. Surv., 



pt. ii, p. 675, pi. clxvi, fig. 2 (non Heer). 

 Sequoia amMgua Uhler, 1901, Trans. Md. Acad. Sci., vol. i (1892), p. 207. 

 Sequoia amMgua Fontaine, 1906, in Ward, Mon. U. S. Geol. Surv., vol. xlviii, 



1905, pp. 272, 281, 538, 555, pi. Ixix, fig. 6; pi. ex, fig. 13. 



