147 



a series of primary nerves extending from the rachis to the ex- 

 tremities of the pinnules and numerous secondary nerves, once 

 forked. Plate 4, Fig. 7. 



Named for Mr. R. C. Hills, largely through whose efforts the 

 collection was acquired. 



In reddish shaly sandstone, Florence, Colo. 



Gleichenia rhombifolia sp. nov. 



General form of frond, also nervation, unknown ; pinnae 

 linear in outline, acute, about 5 mm. in width, composed of sub- 

 quadrate pinnules, the lower ones distinct, acute and curved in- 

 ward at the tips, the upper ones becoming confluent or closely 

 approximated and all of nearly uniform length, giving to the 

 pinnae a delicate, ribbon-like appearance. Plate 3, Fig. 3. 



In reddish shaly sandstone, Florence, Colo. 



Gleichenia delicatula Heer (?), Fl. Foss. Arct. 3 2 : 54. 

 pi. g.f. lie ; pi. 10. f. 16, iy 

 This specimen agrees quite satisfactorily with Heer's Fig. lie 

 above quoted, but not so closely with his other figures, which 

 show pinnae broader at their bases and not so uniform in width 

 throughout as in ours. Further than this, if we determine these 

 to be identical this determination would infer a very extensive 

 vertical range for the species, a range which we would hardly be 

 justified in assuming without question, upon such meager evidence 

 as that afforded by the single fragment represented by our speci- 

 men, although there would be no inconsistency in identifying a 

 species from the Kome beds with one from the Laramie. Plate 



3> Fig- 4- 



In reddish shaly sandstone, Florence, Colo. 



Pecopteris (Cheilanthes) sepulta Newb. (?) Monog. U. S. 

 Geol. Surv. 35 : 12. pi. 62. f. 5, $a, 6. 1898 



Pecopteris {Pliegopteris) sepulta Newb. Proc. U. S. Nat. Mus. 

 5: 506. 1883. 



After some hesitation I have finally decided to refer our speci- 

 men provisionally to this species. The differences are slight and 

 the resemblance is so close that a distinction seems hardly to be 

 warranted. Plate 3, Figs. 5, 5a. 



