348 
FERNS : BRITISH AND FOREIGN. 
and other genera, the roots are naturally of a dark, or 
even quite black colour, and it is known to have been 
considered by some cultivators, not well versed in the 
nature of Ferns, as dead, and accordingly they are totally 
removed, even although with evidence of the plant 
being healthy and vigorous. The healthy state of the 
plant is readily explained, for on examining the nume- 
rous points of the black roots, each will be seen to be 
of a pale colour, which are the active feeders of the 
plant ; and, in shifting, great care should be taken not 
to bruise or injure them. 
The same directions apply to the gigantic Tree 
Ferns and species of Angiojjteris. The soil for them, 
however, should be of a coarser nature when of a size 
to require the largest-sized pots or tubs ; in no case 
is it desirable to give more than three inches extra 
space at one shift, even in the largest pot or tub. In all 
pots above one foot in diameter, the drainage should 
be elevated in the centre. When the shift is large, an 
inverted pot should be placed in the new pot, placing 
a layer of drainage round it, the height of the pot to 
be such that the crocks of the old ball (which must 
not be taken out) rest on the top of the new drainage 
or pot. By this the outer circle of bottom roots are 
not pressed together, or crushed by the weight of the 
ball, which is sure to be the case when the ball is set 
on a level surface, it also keeps the ball to its proper 
height. This mode of drainage has been the constant 
practice at Kewwith all large shifts, not only for Ferns 
but Proteacecs and all fine fibrous-rooted plants, the 
nature of which is to extend outwards and downwards 
through the new soil, ultimately forming a web of 
roots against the sides of the pot. In the ordinary 
