GENERAL CHARACTERISTICS BY 
in sodden masses of decayed vegetation cannot endure 
stagnant moisture about their stems and foliage. This 
is pronouncedly so with plants that have downy or woolly 
foliage, as instanced by most of the Androsaces, and also 
with plants of rosetted growth like the encrusted Saxi- 
frages, Ramondias, Lewisias, etc. 
There are a certain number of very succulent plants 
that apparently require no more soil than will serve as 
anchorage to prevent them being blown from their situ, 
and which absorb practically all their nourishment from 
the atmosphere. Thus, we find Sempervivums massed 
on ledges of rock with nothing more than a thin coating 
of lichen and the humus of their own outspent and 
withered rosettes to root in. ,To establish a colony of 
these plants on a ledge of rock-work in the home garden 
is a simple matter. Get a shovelful of clay and a little 
cow manure, soak until they can be mixed together into 
a mortar-like paste, and throw it down with some force 
on the selected ledge. Whilst still wet press into it a few 
rosettes of the Sempervivum so that any roots they may 
have are embedded in the compost and the foliage just 
rests on the surface, and leave them to establish themselves. 
Arenaria balearica, a plant of slender prostrate stems 
clothed with minute leaves, is another plant that will 
grow upon bare rocks of a porous nature. The stems fix 
themselves to the rock by means of tiny stem-rootlets 
which nourish the plant by extracting moisture from the 
absorbent stone. So closely does the plant grow that 
the surface of foliage reproduces every ridge, bulge and 
depression of the stone beneath it. Veronica canescens 
