VIVIPAROUS AND PROLIFEROUS FERNS. 



the base (such as Marattias), where, unless they happen to be placed under 

 particularly favourable circumstances, although possessing the power of repro- 

 duction, they remain dormant and never develop. 



These viviparous and proliferous characters are not limited to any special 

 genera, nor are they peculiar to Ferns of any particular size or habit ; for, 

 while there are such proliferous pigmies as Asplenium flabellifolium, A. ineiswn 

 (elega?itulum), and Fadyenia prolifera, the gigantic-growing Asplenium di- 

 morplium (A. biforme or A. diver sifolium of commerce), Nephrodium diver gens, 

 Woodwardia orientalis, W. radicans, and numerous other kinds, are examples 

 of large-growing Ferns possessing the same characters. With a view to 

 simplifying their nomenclature, it is advisable to divide these Ferns, according 

 to the different ways in which the characteristic bulbils or young plants are 

 either produced or disposed upon their various organs, into four groups, as 

 follow : 



(1) Plants in which the viviparous character extends over the whole, 

 or over the greater part, of the surface of the leafy portion of the fronds. 



(2) Ferns in which the proliferous character, instead of belonging to 

 the leafy portion of the frond, extends only to its stalk or rachis, which is 

 then covered, to a greater or less degree, with adventitious growth. 



(3) Ferns whose fronds bear one solitary bulbil, situated at or near to 

 their extremity, or whose tailed appendage is formed by the production of a 

 young plant partaking of the same characters as the parent. 



(4) A group exclusively composed of Ferns which have the base of their 

 stalks provided with either stolons, roots, or scales, of a proliferous nature, 

 each of these bearing one or more latent buds or bulbils, which, under favour- 

 able circumstances, never fail to reproduce the parent. 



Group I. 



In the first of these four groups — that comprising Ferns in which the 

 viviparous character extends over the whole or over the greater part of 

 the leafy portion of the fronds— the whole or only a part of their limb 

 is plentifully studded with young plants, all in various stages of formation, 

 from the mere bulbil, no larger than a pin's head, to the small "plantule" 

 furnished with four or five embryo fronds, as is often noticeable in some 



