FERTILISATION AND PROPAGATION. 



137 



Lomaria discolor Upinnaiijida is another rare and beautiful barren Fern, 

 of Australian origin, and one of the most elegant of its genus for decorative 

 purposes. It is a plumose form of the sub -arborescent L. discolor, to which 

 it bears the same relation as Polypodium vulgar.e cambricum does towards 

 P. vulgare. Like those of the species to which this remarkable variety is 

 related, its fronds, which are produced in abundance, spring from the crown 

 of a short, robust stem ; they measure from ljffc. to 2ft, in length, and 

 have a peculiar arching habit, doubtless produced by the weight of the leafy 

 portion, which, instead of being simply pinnate, like those of all other 

 Lomarias, has the pinnae very closely set, so as to overlap each other. 

 This variety produces only pseudo-fertile fronds, which have all the appear- 

 ance of fructification, but which never contain any spores : it consequently 

 remains comparatively scarce. To reproduce it, suckers have to be resorted 

 to : these are very sparingly produced from the base of the trunk, and 

 generally below the surface of the ground. By being taken off, when provided 

 with three or four fronds, but not before, and potted in a light compost 

 containing a little decayed sphagnum, the suckers soon produce young plants, 

 which, when established, grow rapidly. 



The superb Gymnogramme Pearcei robusta, which is a vigorous -growing 

 form of the elegant but very delicate G. Pearcei of Peruvian origin, is another 

 permanently barren Fern, illustrative of the theory that when a plant does not 

 produce seeds its reproductive powers are enhanced in other ways. The 

 original G. Pearcei generally, if not exclusively, produces but a single crown ; 

 but this very interesting variety has a tuft of crowns at the apex of the short 

 caudex, from which many stipes arise, giving the plant a denser habit, and 

 the appearance of being better furnished, than the original type. This 

 multiplicity of crowns is the exception among Gymnogrammes, and furnishes 

 us with the only means of propagation applicable to this particular variety, 

 whose tall, triangular, bright green fronds are nearly as finely cut as those 

 of the species from which it is a seedling, but in other respects it is larger 

 in all its parts, much more robust, and of much freer growth. 



Accidentally or occasionally, fertile Ferns are found amongst exotic as 

 well as amongst British kinds, and that partial character again is mostly 

 restricted to plumose forms of species naturally provided with plain foliage. 

 We will only give as illustrations three of the forms most striking, on account 



