﻿MR. JOHN SCOTT ON THE TREE FERNS OF BRITISH SIKKIM. 39 



Gareedhovra 



in the forests of the Dulha Jhar, from two to three miles south of the Balasun river, and about six 



miles from Punkabaree. 



An interesting species, with an exceedingly proliferous and occasionally dichotomous 

 caudex. In the Sikkim valleys it varies from 6 to 15 feet in height, and in this respect 

 differs from the lofty specimens of the Khasia hills, Malayan peninsula (50 feet high, 

 Wall.) and islands. It is, as remarked in the Sp. Eil., " so variable in the form and 

 size of the pinnules in our copious specimens, that it is scarcely possible to dejine them 



in words " *' on some specimens 2-4 inches long by J an inch broad, on others 6 



inches long and 1 inch broad ; segments also varying much in length and in the deptli 



I may add, it also varies much in the venation, and even in the position 



of the 



a 



Sikkim 



of the sori, though the more or less Y-shape is very characteristic. These variations 

 shown in many figures of the pinnae of this species from two plants which I collected 



In the first three specimens, from one plant, the venation varies from simple 

 to forked, with the veinlets occasionally uniting again before they reach the margin ; sori 

 on one segment parallel to and placed nearly on the margin, in the other tending to the 

 triangular arrangement, though distant from the costule. In the series from the other 

 plant the venation is simple and forked, the sori are marginal and ohliquely tending 

 towards the costule* 



DESCIMPTIOJSI OE THE PLATES. 



Plate I. 



slender 



ihowing 



towards the upper extremity^ and the reduction of the interspaces between the fronds — b being 



01 origin of th< 

 given off. Nat 



I 



30 



epidermal 



different 



enren 



chyma (c'), a stratum of parenchyma (c*), and a central layer of pale-brown trachenchyma 



mass, with imbedded fibro-vascular bundles, e. Nat 



Fig. 3. Longitudinal section of the woody laminae of the above prepared by maceration^ showing the 



arrangement and shape of the frond-meshes — with recurved margins, from which branches are 

 given off to the latter. Nat. size* 



Fig. 4. Transverse section of the caudex of Hemitelia decipiens; the references are the same as in fig, 2; 



adventitious roots concretions of cellular tissue resembling the free vascular bundles. ^Nat. size. 



Plate II. 



Figs. 1 & 2. Lower and upper surfaces of a half-inch-thick section of the caudex of Alsophila comosa at 



