122 TNIOPTERIS. 
Genus TZENIOPTERIS, Brongniart. 
[Prodrome, 1828, p. 61.] 
Brongniart defines the genus Zeniopteris in his ‘‘ Histoire” 
as follows :— 
‘* Folia simplicia integerrima, nervo medio crasso rigido, ner- 
vulis perpendicularibus simplicibus vel basi furcatis. Fructificatio 
punctiformis.”’! 
The same author, in his later work,? compares the genus with 
various recent ferns, and notes the resemblance of some specimens 
of Teniopteris vittata, Brong., to Oleandra; a resemblance which 
Schimper has given expression to in the case of some Teeniopteroid 
leaves by the adoption of the name Oleandridium. 
In Schenk’s definition of Teniopter’s, a genus which he places 
in the Marattiacee, it is described as having ‘“‘ Folia petiolata 
bipinnata.’”’* Saporta, following Brongniart’s original diagnosis, 
describes the fronds as usually simple, and considerably extends 
the generic definition’ :— 
‘“‘Frondes plerumque simplices et tune petiolo valido instructs 
(rarius pinnatim composite) elongate toeniate lanceolate vel 
lingulatee nervo marginali cincte; costa media subtus crassa 
semiteres supra plus minusve gracilis; nervi secundarii plurimi 
e costa media sub angulo acuto exeuntes mox subito horizontales 
numerosissimi simplices vel sepius a basi pluries furcato-dichotomi 
usque ad marginem nerviformem recto tramite excurrentes. 
Fructificatio adhuc ignota aut punctiformis, soris punctiformibus 
totam paginam frondis inferiorem occupantibus.” 
He remarks that the exact definition of Zeniopterts constitutes 
one of the difficulties of fossil botany. The above diagnosis is 
more comprehensive than the description given by some authors 
of the same genus; the genus Oleandridiwm of Schenk is included 
by Saporta under the provisional and safer name instituted by 
Brongniart. Attention is drawn to the Teniopteroid form which 
is occasionally assumed by the genus WVilssonda, Brong.; but there 
1 Hist. vég. foss. p. 262. 
? Tableau, p. 21. 
3 Fl. foss. Grenz. Keup.-Lias, p. 99. 
4 Pal, Frang. vol. i. 1873, p. 430. 
