256 THE BOOK OF CHOICE FERNS. 



and species native of India are well represented by P. ensiformis, P. longi- 

 plnnula, P. ludens, &c., as distinct from each other as they are from species 

 of other origin. 



Culture. 



The plants belonging to a genus with such an extensive habitat must 

 of necessity require diiferent treatment according to the locality whence they 

 have been introduced ; consequently, while we have several species of Pteris 

 which thrive in stove temperature only, and one at least which is. perfectly 

 hardy, there are others — and these indeed are the majority — for which a 

 greenhouse temperature is the most suitable. Pterises are not fastidious as 

 regards soil : and a mixture of two parts peat, one part loam, and one part 

 sand suits most of them. The majority of them thrive as well in a place 

 exposed to strong light as in a shady one, but this does not apply to the 

 beautifully-variegated P. quadriaurlta argyrcea, P. cretica albp-lineata, P. 

 aspericaulis tricolor., and P. ensiformis Victories, all of which, either in their 

 natural habitats or under cultivation, need a subdued light. The cause of 

 these plants being frequently met with in a stunted condition and having 

 a burnt appearance is generally attributable to the effects of strong light, and 

 this is readily understood when we consider the natural conditions under 

 which the plants flourish, being always found in the dense shade of forests 

 where the annual rainfall is very heavy, and rarely if ever growing in Bamboo 

 forests where the shade is partial only. 



With the exception of a few species provided with creeping rhizomes, 

 and which may be propagated by division, all Pterises are readily increased 

 from spores, which are abundantly produced and germinate very freely. 



Several species of this genus have, under culture, developed to a marked 

 degree a tendency to variation ; thus we have lightly -crested and heavily- 

 tasselled forms of P. cristata and P. serrulata ; the robust-growing P. tremula 

 has also produced crested, tasselled, and variegated forms ; ^vllile in P. cretica 

 Ouvrardi we have a plant so far removed from the species from which it is 

 supposed to be issue as to possess a habit entirely difterent from any other 

 known species. Most, if not all, the varieties so created artificially also possess 

 a power of reproduction which is equal to that of the typical species. 



