12 JOURNAL OF THE ROYAL HORTICULTURAL SOCIETY. 
in the selection of a suitable compost. Clean fibre, either Osmunda, 
A. I., or first-class peat, kept moist by the addition of a small quantity 
of living Sphagnum, forms the best material. A few clean oak- 
leaves roughly chopped up or rubbed through a riddle may with 
advantage be added to the compost intended for small pots, but with 
large plants, requiring re-potting less frequently, the leaves are best 
omitted, as they are likely to cause a sodden condition by holding too 
much water. The smaller the pot and amount of compost so much 
the quicker does it become dry, hence it is advisable to include 
a larger proportion of Sphagnum, especially near the surface; 
medium-sized pots answer well when the moss is placed only in the 
upper portion of the compost, while many of the plants in the largest 
pots thrive well in only fibrous material. But in this matter nothing 
definite can be said, so much depends on the amount of atmospheric 
moisture, the structure of the house, and the actual means adopted 
by the one in charge of the collection. 
