236 MESOZOIC FLORAS OF UNITED STATES. 



This plant was formerly determined by me as a new species of 

 x4ngiopteridium, for which the specific name oregonense was suggested. 

 With this name it was quoted by Mr. Stanton in Bulletin No. 133 of 

 the United States Geological Survey. A careful reexamination of it 

 shows anastomosis of the nerves, which indicates that it is not Angiop- 

 teridium, but a new species of Sagenopteris. 



This fern was found in three specimens, two at the localit}^ near 

 Riddles, Oreg., and one at locality No. 3. One of the specimens found 

 near Riddles has an excellently preserved imprint of an entire lateral 

 pinnule. The other shows a nearly entire middle pinnule. The former 

 is represented in PL LXV, Fig. 36, and the latter in Fig. 37. Fig. 38 

 represents the .specimen originally referred to S. latifolia. 



Sagenopteris elliptica Fontaine. 



PI. LXV, Figs. 39, 40. 



1889. Sagenopteris eUiptica Font. : Potomac Flora (Monogr. U. S. Geol. Siirv., 

 Vol. XV), p. 149, pi. xxviii, figs. 9, 11-1.5, 1.5a, 16, 16a. 



Several specimens of a fern were found that seem to be Sagenopteris 

 elliptica Font., of the Lower Potomac formation of Virginia. The fossils 

 are in the form of detached pinnules, which are, in most cases, entire. 

 These have a close resemblance to the Potomac fossil and can hardly be a 

 different species from it. The pinnules var}'- a good deal in size. The 

 smallest are rather smaller than any seen of the Potomac plant, and the 

 largest are of the same size with the largest of that plant. Two or three of 

 the smaller-sized pinnules have a more obtuse tip than any of the Potomac 

 fossils. One of these, given in PI. LXV, Fig. 40, is almost spatulate in 

 form. Possibly these may belong to a different species of Sagenopteris. 

 The imprints as a rule show the elongate elliptical form of the Virginia 

 plant, with the midrib prolonged beyond the middle of the pinnule. PI. 

 LXV, Fig. 39, gives a pinnule of the largest size, which shows well these 

 features. It is at the base somewhat unsymmetrical, the lamina on one 

 side being broader than on the other, owing probably to the fact that this 

 is a lateral pinnule. 



The plant seems to be more common than the other species of Sage- 

 nopteris, but still is not ver}^ common. It occurs at localities Nos. 1, 18, 19, 

 and 21. 



