124 TH NIOPTERIS. 
selves, or from the close association of sterile and fertile leaves, 
it is much better to retain the ‘‘ convenient and non-committal 
genus Zeniopteris.” 
I propose, therefore, to use the generic term Teniopteris in 
a wider sense, and in this respect to follow Nathorst,! who has 
taken the safer course and included under this genus such other 
generic names as Oleandridium, Angiopteridium, Marattiopsis, 
Daneopsis, etc. In taking this view I am simply following the 
same plan as in the case of other provisional names such as 
Cladophlebis, ete. In dealing with such leaf-forms as come 
under the Tzeniopteroid type, it is especially important to wait 
for trustworthy taxonomic evidence before making use of names 
which imply close relationship or identity with existing genera ; 
the grounds for this caution are to be found in the numerous 
recent ferns which have leaves or leaf-segments of the Tzenio- 
pteroid pattern.? 
In Hooker’s ‘‘Genera Filicum’’* we find the name Zeniopteris 
applied to a recent fern, 7. Forbesti, Hook., from Mozambique. 
Following the example of Fée,‘ Hooker, in his later writings, 
includes this genus as a synonym of Vittaria.’ 
We may broadly define Zeniopteris as follows:—Frond simple 
or pinnate, usually lanceolate or linear-lanceolate, apex acute or 
occasionally obtusely terminated ; a well-marked midrib from 
which lateral veins are given off either at right angles or more 
or less obliquely; these may be unbranched or acutely forked 
as they pass towards the leaf margin. 
In an allied venation type, Phyllopteris, Brong., the lateral 
veins are much more oblique, more curved, and repeatedly forked. 
The task of naming the various fragments of Zendopteris in 
the Museum Collection has proved a difficult one, and, owing to 
the meagre nature of the specimens, it is almost impossible to 
arrive at any very satisfactory or definite results. In none of 
the examples are there any traces of sori, nor have we any 
opportunity of obtaining information as to the general habit of 
the plants, all the fragments being portions of detached leaves. 
Sver. Geol. Undersékn. 4to. Flor. Bjuf, 1878-1886. 
See also Fontaine’s species of Anomozamites, Potomac Flora, p. 67. 
Pl. lxxvi. B. 
Genera Filicum, p. 86. 
Species Filicum, vol. vy. 1864, p. 176. 
ao fF wo Nn eS 
