72 



through the winter in the open air in the eastern parts of England. 

 The amateur grower will manage better with it as a house plant, 

 in which case the season of dearth is that in which its delicate 

 fronds are most attractive to the eye. It will flourish in the stove 

 and greenhouse, but in the inhabited room requires the cover of a 

 bell-glass, and is admirably adapted for growing in the close or 

 Wardian case. It ought never to be exposed to the sun. In 

 regard to soil, I have found it succeed well in the same compost 

 as that recommended for Asplenium marinum. 



Genus 14. TRICHOMANES. 



GEN. CHAR. Sori marginal. Thecse sessile around columnar fili- 

 form receptacles, which are extramarginal extensions of the 

 anterior branches of the lateral veins, within open cylindrical 

 or suburceolate involucres of the same texture as the frond. 



The generic name, borrowed from Dioscorides, was applied by 

 the Greeks to some species of ferns, probably Asplenium Tricho- 

 manes, and is not unaptly transferred to these, considering the 

 arbitrary allotment of botanical names generally ; the prefix, from 

 Opl, rpixps, a hair or bristle, bearing allusion to the hair-like 

 receptacles of the sori, while the termination, from pavos, soft, 

 thin, or flexible, accords with the character of the fronds ; a con- 

 venient, though forced, interpretation, that may suffice in the 

 absence of one more consistent. 



The plants comprised under this and the following genus. 

 Hymenophyllum, are remarkably different from the other ferns in 

 the development of their fructification, in habit, and in the texture 

 of the frond, which latter is membranaceous, and under the micro- 

 scope very beautifully reticulated. They grow only in very moist 

 and shaded places ; indeed, their organization is not adapted to 

 support those ordinary changes in the hygrometric condition of 

 the atmosphere that do not visibly affect vegetation in the aggre- 

 gate; their delicate fronds become brown, and shrivel when ex- 

 posed even to a few hours' drought, and they resist all customary 

 modes of cultivation, in consequence of the excess of light and 

 insufficiency of moisture in the surrounding air that are their 

 usual concomitants. The numerous species of both genera are 

 almost all tropical, inhabiting the deep recesses of the forests of 

 hot climates, where, in an atmosphere loaded with vapour, they 

 flourish, as well as in similar situations to those to which they are 

 confined in Europe. 



TRICHOMANES RADICANS. European Bristle Fern. TAB. XLI. 

 Fronds tri-quadripinnatifid, glabrous, deltoid-ovate or lanceo- 



