353 . Systematic Paleontology 



Ctenoptekis insignis Fontaine 



Ctenopteris insignis Font., 1890, Mon. U. S. Geol. Surv., vol. xv, 1889, p. 



156, pi. Ixi, figs. 4, 5; pi. Ixii, fig. 1; pi. Ixiii, figs. 1, 2. 

 Ctenopteris virginiensis Font., 1890, Ihid., p. 157, pi. 1x11, fig. 4; pi. Ixv, 



fig. 1; pi. Ixvi, fig. 4. 

 Ctenopteris minor Font., 1890, Ibid., pi. Ixvii, fig. 3. 

 Ctenopteris insignis Font., 1906, in Ward, Mon. U. S. Geol. Surv., vol. xlviii, 



1905, p. 521, pi. cxii, fig. 7. 

 Zamiopsis insignis Font., 1906, in Ward, Mon. U. S. Geol. Surv., vol. xlviii, 



1905, p. 525, pi. cxiii, figs. 4, 5. . 



Description. — "Frond large, arborescent, bipinnate or tripinnate; 

 principal racliis very strong, striate ; ultimate pinnae with strong, rigid 

 rachises, alternate, terminating in a lobed segment, the pinnules passing 

 into lobes more or less united toward the ends of the ultimate "pinnge ; 

 pinnules thick and leathery, those of the lower and middle portions of 

 the pinnae attached by the entire base, slightly decurrent, separate, cut 

 away obliquely above, alternate to subopposite, gradually diminishing 

 towards the summit of the pinnEe in size and depth of toothing, 

 not sensibly narrowed at base, oblong-acute, curved slightly forward, 

 terminating in a large ovate to sub triangular acute tooth. The pin- 

 nules usually show two acute or spinous teeth on each side, a couple 

 near the base, and a second couple near or at the summit of the pinnule, 

 the associated members of the couples being opposite or subopposite. 

 Sometimes there is an additional tooth on the posterior margin below 

 the upper one, and sometimes the terminal tooth is enlarged to an 

 oblong lobe, which is slightly notched; nerves several, departing separ- 

 ately from the principal rachis along the entire width of the base of the 

 pinnule, the outermost ones once forking and curving outwards, the 

 inner ones forking deeply several times and slightly diverging flabel- 

 lately, the ultimate branches nearly or quite parallel, long, and slender/' 

 —Fontaine, 1890. . 



The only satisfactory specimens of this plant come from Fredericks- 

 .burg, where it is not uncommon, but usually rather indistinctly pre- 

 served. The additional occurrences are based on small fragments. 



