FONTAINE.] THE OROVILLE FLORA. 3538 
Genus DIDYMOSORUS Debey and Ettingshausen. 
DipyMosorus ? BINDRABUNENSIS ACUTIFOLIUS Fontaine. 
Pl. LVI, Figs. 2, 3. 
1860. Pecopteris (Gleichenites) linearis Oldh.: Mem. Geol. Survey of India, Vol. II, 
Pt. II, p. 324. 
1863. Pecopteris (Gleichenites) gleichenoides Oldh. and Morr.: Op. cit., Pal. Ind., Ser. 
I, Foss. Fl. Gondw. Syst., Vol. I, Pt. I, Foss. Fl. Rajmahal Series, p. 
45, pl. xxv; pl. xxvi, figs. 1, 3. 
1869. Gileichenia bindrabunensis Schimp.: Traité de Pal. Vég., Vol. I, p. 670. 
1875. Gileichenites bindrabunensis (Schimp.) Feistm.: Verh. d, k.-k. Geol. Reichsanst., 
Wien, Jahrg. 1875, p. 190. 
1877. Gleichenites (Gleichenia) bindrabunensis (Schimp.) Feistm.: Mem. Geol. Survey 
of India, Pal. Ind., Ser. II, Foss. Fl. Gondw. Syst., Vol. I, Pt. II, p. 93 
(Jur. Fl. Rajm. Group, p. 41). . 
1888. Didymosorus ? gleichenoides (Oldh. and Morr.) Etheridge, var.: Proc. Linn. 
Soc. N. 8. W., 2d Ser., Vol. III, Pt. IIT, p. 1308, pl. xxxviii, fig. 3. 
1892. Didymosorus ? gleichenioides (Oldh. and Morr.) Jack and Etheridge, var.: 
Geology and Paleontology of Queensland and New Guinea, p. 557.! 
Only a small fragment of this plant was found at the locality ‘‘In 
the bed of a ravine that leads from the Banner mine,” etc. The speci- 
men is an imprint of a small fragment of the terminal portion of a 
penultimate pinna that contains several ultimate pinne. The latter are 
very small and narrowly linear. The largest are about 2 cm. long and 
not more than 4 mm. wide. They are not very distinctly preserved, as 
they occur on indurated tuff. They are also somewhat distorted by 
pressure. The nervation was not made out. The plant resembles 
Pecopteris gleichenoides Oldh. and Morr.’ It is probably an acute 
form of the Indian fern. This latter has pinnules with obtuse tips. 
It is most like the plant from the Rajmahal series figured on pl. xxvi, 
fig. 8, but is smaller than that. The narrow pinne are cut into narrow 
ovate-acute lobes or pinnules. Should it prove to be a form of the 
Indian fern it might be called variety acutifolius. 
1Jack and Etheridge here change the spelling of the specific name so that the combination becomes 
identical with Didymosorus gleichenioides Debey and Ettinghausen in their memoir, Die Urweltlichen 
Acrobryen des Kreidebirges von Aachen und Maestricht, p. 10 (Denkschr. Wien. Akad., Vol. XVII, p. 
190, pl. i, figs. 1-5), with which no one has compared it, and which isa different plant. Neither Oldham 
and Morris nor Etheridge seemed to have observed that Debey and Ettinghausen gave this name to one 
of the original forms on which they based the genus, although these authors refer to this memoir and 
call attention to other species. As the specific name linearis is also preoccupied, the only remaining 
name is that of Schimper, and this therefore must be retained. L. F. W. 
- Fossil Flora of the Rajmahal Series, p. 45, pl. xxv; pl. xxvi, figs. 1, 3. 
20 GEOL, PT 2 23 
