14 THE LATER EXTINCT FLORAS OF NORTH AMERICA. 



Sphenopteris coreugata Newb. 

 PI. I, fig. 6. 



Ann. N. Y. Lye. Nat. Hist., Vol. IX (April, 1868), p. 10; Ills. Cret. and Tert. PI. 



(1878), PI. II, fig. 6. 

 Hymenophyllum cretaceum Lesq. Hayclen's Ann. Rept., 1872 [1873], p. 421; Cret. 



Fl. (1883), p. 45, PL XXIX, fig. 6 [excl. PI. I, figs. 3, 4]. 



" Form of frond unknown; pinnules ovate or cuneiform, narrowed at 

 the base, obtuse, lobed, often plicated longitudinally; nerves distinct, 

 dichotomously branching- from the base. 



" The specimens of this fossil collected by Dr. Hay den are fragmen- 

 tary and imperfect, but quite sufficient to show it to be different from any 

 described species." 



Since the above was written Lesquereux has published in his Cre- 

 taceous Flora descriptions of a fern from the Dakota sandstones, at Fort 

 Harker, which he calls Hymenophyllum cretaceum. Of this he gives several 

 figures on PI. I, and another on PL XXIX. Of these the latter certainly 

 represents our species, which is easily recognized by the wedge-shaped 

 subdivisions and the plicate or corrugated surface; but the specimens 

 figured on PL I belong to a different species, of which the frond was 

 membranous and the rachis winged, and which approached much nearer to 

 the living Hymenophyllum. 



Formation and locality: Cretaceous (Dakota group). Blackbird Hill, 

 Nebraska. 



Order EQUISETACE^E. 



Equisetum Oregonense Newb. 

 Pi. LXV, fig. 7. 

 Proc. IT. S. Nat. Mus., Vol. V (March 21, 1883), p. 503. 



"Stem robust, 3 centimeters wide, longitudinal flutings numerous, 

 about 24 in a half circumference; joints 5 centimeters distant; teeth trian- 

 gular, short." 



This species, collected by Rev. Thomas Condon, at Currant Creek, 

 Oregon, is imperfectly represented in the collection, but there is enough of 

 it to show it to be distinct from any other fossil yet found. It exceeds in 

 magnitude any Tertiary species hitherto described in 'this country, and 



