132 



GBEENHOUSE FEBNS. 



Like A. marinum, there are several other British Ferns 

 which may with more ease be cultivated in a greenhouse than 

 out of doors. It is only in favourable positions that such 

 plants as A. tricJiomanes, A. fontanum, A. septentrionale, 

 A. lanceolatum, A. germanicum (or A. alternifoUum) , A. viride, 

 or even the more common A. Ruta-muraria, can be induced to 

 grow freely in the hardy fernery ; but they make very pretty 

 little ornaments grown in pots in the greenhouse. 



There are some other greenhouse Aspleniums, among which 

 are A. acutum, a South-European species, A. rutcefolium, from 

 the Cape of Good Hope and Natal, A. pinnatifidum, a small- 

 growing species, and others. 



BALANTIUM. 



BALANTIUM CULCITUM (Cushion), Fig. 61. A curious, 



scarce, handsome Fern, 

 the only one of the genus 

 in cultivation. It is a 

 native of Madeira. The 

 fronds are many -times- 

 divided, growing 3 feet 

 high ; the pinnae are 

 nearly triangular, with 

 sharp points, and deeply 

 toothed at the edges. The 

 spore-masses are curious, 

 in the shape of an oblong 

 purse : hence the generic 

 name, balantium, a purse. 

 The rootstock is decum- 

 bent, or laid down in the 

 earth, is very thick, and 



rather creeping. By this it may be increased wherever there 



is a bud formed below the leading shoot. 



Fig. 61. Balantium culcitum. (Pinna na- 

 tural size ; indusium magnified.) 



