THE MOUNTAIN ItLADDKIt FERN. 



unequal, ascending, the lower i>air considerably largest, two inches and a half long, obliquely ovate, 

 the posterior pinnules twice as long as the anterior ones; some of the other pinme arc also unequal* 

 Bided, the posterior pinnules being largest, but at the top this difference is not manifest. 

 Pinnule* (the larger posterior ones) ovate, pinnate, or the smaller upper ones piniiatifid. Pinnttlets 

 (basal) of the larger pinnules, ovate with a distinct narrowed stalk-like attachment, but connected by a 

 narrow wing, piniiatifid, with oblong-ovate obtuse lobes cut into linear teeth which are generally bifid at 

 the extremity. In its ultimate divisions it is thus very much like C. regia. 



Vctudion of the pinnules, consisting of a nearly straight midvein, with alternate veins directed one 

 into each lobe ; a venule is given off towards the teeth, ami is continued to the margin, where it is lost 

 in the sinus formed by the biiid apex of the tooth, thus ending in a depression rather than a projection 

 of the margin. 



Fructification occupying the whole under surface, &ori consisting of numerous moderate sized, 

 roundish masses of spore-cases, medial on the veins, indusiato. Indimum, a delicate transparent, con- 

 ceive, subrotund membrane, irregular at the margin, placed at tho back of the sorus, and soon 

 obliterated. Spore-cam obovatc. Spore* oblong murieate. 



Duration. The rhizome is perennial The fronds are annual, ami appear about May, perishing 

 in autumn. 



This plant is at once known from the other British species of Cystojtteris by its long creeping 

 rhizome, and its triangular and tripinnate fragile fronds. It has much more the aspect of Pott/podium 

 Aryoptoris, for which it might, perhaps, be mistaken,— the more readily, as ita indusia become soon 

 obliterated, and the sori then seem to consist of round naked masses of spore-cases. It is, however, not 

 three-branched, as that is, and is more divided. 



This plant has hitherto proved difficult to cultivate, probably on account of tho slight information 

 which was possessed of the peculiarities of its native habitats. Now, however, that it is known that its 

 rhizomes thread their way on the ledges of dripping rocks, among beds of sphagnum, it may be 

 supposed that less difficulty will be experienced. These natural conditions suggest tho employment of 

 (1,) broad shallow vessels; (2,) a very open medium for the roots, such as light turfy peat and 

 sphagnum intermixed and blended with sand; and (3,) constantly abundant, yet not stagnant, moisture. 

 The creeping rhizomes afford every facility for propagation. 



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