344 OLDER MESOZOIC FLORAS OF UNITED STATES. 
mens from the lovality ‘‘Bank of Feather River,” etc. It is too 
fragmentary and too poorly preserved to permit its character to be 
made out fully. It most resembles the Zhyrsopteris Maakiana of 
Heer, from the Jurassic of Siberia,’ but the pinnules are more entire, 
probably because they are higher up on the frond. 
The most complete specimen is the one figured. This occurs on 
a fragment of indurated tuff that has the physical character of sand- 
stone, hence the imprint is not distinct and is somewhat distorted. 
This imprint shows a portion of a penultimate pinna, with several 
ultimate pinne on each side of the rachis. These are lanceolate in 
form and alternate in position, with lobes and teeth cut obliquely into 
an oblong or ovate shape. The basal upper pinnules are decidedly 
larger than any of the rest. Toward the ends of the ultimate pinne 
the pinnules become entire, or nearly so. The incision of the lamina 
is made to varying depths, according to position, so that the lobes 
pass to teeth higher up. — 
Genus ADIANTITES Géppert. 
ADIANTITES OROVILLENSIS Fontaine. 
Pl. XLIX, Figs. 2, 3. 
1896. Adiantites orovillensis Font.: Am. Jour. Sci., 4th Ser., Vol. II, p. 274. 
Frond tripinnate, primary and secondary rachises strong and rigid. 
The principal rachis was seen with a thickness up to 5 mm. The 
primary pinne are long and lanceolate in form. Their mode of inser- 
tion was not seen. The ultimate pinne are subopposite and oblong in 
form, with 4 to 5 pinnules on a side that do not diminish much 
in size from the base to the summit of the pinne. They are termi- 
nated by a spatulate pinnule that is nearly as large as the rest, an 
unusual feature in ferns. The pinnules are round to reniform in shape 
and subopposite. They are rather remote and decurrent to form a 
narrow wing. They are small, about 6 mm. wide and 4 mm. in height. 
Their nervation was not clearly made out, but seems to be composed 
of a bundle that spreads in the lamina of the pinnule, in a flabellate 
manner, forking once in each branch. 
This elegant little fern was found in only one specimen at the local- 
ity ‘‘Bank of Feather River, one-half mile south of the Banner 
mine.” Pl. XLIX, Fig. 2, gives this specimen, and Fig. 3 repre- 
sents one of the pinnules magnified to show details. 
This plant seems to be new and not very near any described form. 
1 Flora Foss. Arct., Vol. IV, Beitrige zur Jura-Flora Ostsib. und des Amurlandes, p. 31, pl. i, fig. la; 
pl. ii, fig. 6. 
