CHARACTERS OF TRIBES AND GENERA. 171 
Gleichenece and Cyathee, with either of which it has no 
natural relationship in habit. This may be termed a truly 
paradoxical Fern, for I find it difficult to fix its position in 
any sequence of genera; its partially reticulated sori 
seem to point to Hemionites, and the form of its fertile 
segments to Llavea and Allosorus, I therefore place it in 
proximity to these genera. 
Sp. C. thalictroides, Brongn. (v v.) (Parkeria Lockharti, 
Hook. and Grev., Ic. Fil., t. 97). 
Oss.—In the Fern houses at Kew this Fern sprouted 
abundantly on all moist surfaces, and grew luxuriantly in 
the Victoria Lily tanks. 
Tribe 10,—VITTARIEA (Plate 10). 
Fronds simple, entire. Veins simple, reticulated or 
compound anastomosing, combined at the margin in a 
sporangiferous receptacle, which is seated in a slit or 
groove. 
Oss.— This tribe contains about a dozen species of grass- 
like Ferns, and as they do not well naturally associate with 
other genera I follow Presl (in part) in ranking Viltariec 
as a distinct tribe. Setting aside the difference of venation 
as a divisional character, they would then rank with the 
genera of the tribe Hymenolepidiec. 
80.—VirrariA, Sm. (1793), Hook. Sp. Fil. 
.. Haplopteris, Pr., 1836; Teniopsis, J. Sm., 1841. 
Vernation uniserial, sarmentum, short, furnished with 
hyaline scales. Fronds contiguous, cæspitose, simple, linear, | 
grass or tape like, from a few inches to 2 or 3 feet in. : 
length, often pendulous or rigid sub-erect. Veins simple, de 
