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THE BOOK OF CHOICE FERNS. 



which, under favourable circumstances, never fail to reproduce the parent — we 

 ■find that, compared with the three other Proliferous groups already described, 

 it is a very small one indeed. Besides the Angiopteris, all the Marattias, and 

 part of the Platyceriums and Polypodiums known to commerce, it comprises 

 only several Nephrolepis and Adiantums. 



The Nephrolepis are all provided with long, wiry stolons or underground 

 rhizomes, which are more or less proliferous, and which, when touching the 

 ground, or when allowed to hang down in a damp atmosphere, produce, at 

 irregular intervals, bulbils, which soon develop into young plants in all 

 respects resembling their parents. Several kinds, such as N. cordifolia 

 (tuberosa), N. pluma, N. undulata, and N. Bausei, bear some perfect tubers, by 

 which they may also be propagated ; but as, with the exception of the first- 

 named of these species, all are of a deciduous nature, great care must be 

 taken that, even when deprived of their foliage, the plants shall have their 

 tubers kept in a moderately moist state, otherwise they will cease to live long 

 before the time comes for them to start into growth again. 



When proliferous, the Platyceriums show that character exclusively on 

 their roots. It is, however, interesting to note that, although the roots of 

 P. alcicorne are frequently met with perfectly covered with adventitious growths, 

 that peculiar character is shown but very sparingly in P. a. major, P. oethio- 

 picum (stemmaria) , P. biforme, and P. Willinckii ; while in the cases of 

 P. grande and P. Wallichii, although the greatest attention has been paid to 

 the subject, there is no record of their roots ever having produced young 

 plants in either small or large quantities. 



Plantules are frequently found on the roots of Poly podium loriceum and 

 its variety pectinatum ; while those of Hypolepis (Cheilanthes) Bergiana are also 

 very proliferous. Several members of the genus Adiantum are proliferous on 

 their roots — principally A. Moorei (A. amabile of commerce), A. cyclosorum, 

 A. diaphanum (setulosum) , A. tinctum roseum, &c, in which no real rhizomes can 

 be detected, the proliferous bud being situated on the root itself, or, at most, 

 on a sort of stolon which emanates from the base of the crown, and the 

 extension of which is indefinite. 



As to Angiopteris and Marattia, both of which genera are natives of 

 swampy places, the proliferation in their cases is most peculiar. All of them 

 have their fronds, which are of a very fleshy substance, surrounded at their 



