42 
Choice Ferns for Amateurs. 
will be secured. Although these will come up 
under cold treatment, the influence of a little arti- 
ficial heat greatly assists development. 
Other Methods of Increase. 
The tubercles produced at the roots of certain 
ISTephrolepis offer another means of reproduction, 
and one that is most valuable in the propagation of 
iY. 2^^"^^"^^) Bausei, &c., which, being of a de- 
ciduous nature, would otherwise have to be increased 
exclusively from spores. Their tubercles, which are 
produced in abundance, remain in the ground at rest 
fully three months after the foliage has died down — 
in November or December — and if the soil in the 
meantime is kept moderately moist, but not wet, 
these tubercles retain their vitality until March, 
when, by being potted off singly (in small pots at 
first) they will, during the season, and with suc- 
cessive pottings, make very pretty young plants, 
similar to those produced from the stolons with 
which all tuberless and evergreen Nephrolepis are 
provided. 
However great may be the advantages derived 
from the propagation of Ferns from spores, there 
are some instances in which that mode of increase 
is practically impossible, as there are species and 
varieties permanently barren, or at least so far as 
plants subjected to cultivation are concerned. 
Usually this character is most commonly exhibited in 
plumose forms of different species, British and exotic. 
Plumation may be considered the most beautiful 
type of variation. It consists in either a much more 
delicate division and growth of the ultimate sections 
of the frond than that of the common species, or in 
a greater leafy development. Ferns partaking of 
the plumose character are usually either partially or 
entirely barren, the reproductive vigour of the plant, 
exactly as is the case with flowering plants bearing 
double flowers, being apparently affected by such 
development. It is beyond dispute that if spores 
are not, or are only very sparingly, formed, the 
reproductive powers of such plants are much more 
