no 
FLORA AND SYLVA 
of Europe. Dr. Purpus has also placed 
these plants within the reach of private 
growers by furnishing such firms as 
Spath of Berlin, and De Laet of Contich 
near Antwerp, with the kinds now in 
commerce, though many others are yet 
unclassed and without name . The entire 
collection contains upwards of loo 
kinds of Cacti (species and varieties) 
of proved hardiness at Darmstadt, and 
consequently throughout Central Eu- 
rope, many of them plants of real beauty, 
and of value for our rock and wall 
gardens. Amongst them is an Agave 
— A. Parryi — found at an elevation of 
7,000 feet in the mountains of Arizona, 
and perfectly hardy with us in places 
where the famous Agave Utahensis has 
perished winter after winter. Among 
the plants already introduced to gar- 
dens, the Opuntias hold the first place. 
Several kinds are altogether different 
from 0. vulgay^is^ and there are some 
in which the flowers are not only red, 
but bright scarlet — a colour previously 
unknown among hardy Opuntias. 
The original collection at Darmstadt 
fills a large rock-garden, composed of 
limestone blocks and covering nearly 
1 00 square metres of ground. Dr. Pur- 
pus considers the use of limestone as 
important if not essential for these plants , 
all of them being found upon rocks and 
in soils of this nature. In many of the 
botanical gardens of Germany which I 
visited in 1904, a great feature is now 
made of these hardy Cacti, and their 
value is already well seen at Giessen — 
where there is a very fine collection — 
at Jena, Leipzig, Magdebourg, Dussel- 
dorf, and many other places in which 
Kinds. 
they seem to thrive to perfection. Since 
the death of M. Marc Micheli, the col- 
lection at the Jardin d'Acclimatation, 
Floraire, has been the only one existing 
in the neighbourhood of Geneva, and it 
is of this that I purpose speaking more 
particularly. The first selection received 
from Herr Spath was subsequently en- 
larged by Dr. Purpus and others, until 
we are now in possession of an excellent 
collection, recently brought up to date 
by valuable additions from M. De Laet, 
— the purchaser of the entire private 
collection of Dr. Purpus. 
In glancing rapidly over these 
gains, we find that the genus 
Opimtia holds the place of honour 
among hardy Cacti. Such plants as 
Rchiuocactus Simp s on Cereus viridi- 
Jiorus^ and Mammillarias inissouriensis 
and radiosa vivipara.^ are more interest- 
ing than beautiful in their flowers, attrac- 
tion lying rather in the pretty little 
coloured fruits by which these are suc- 
ceeded , and their qua i nt general appear- 
ance. Ec/iinocereus or better Cereus 
Phoeniceus^ of which we give an illus- 
tration, is however one of the best of 
the hardy Cacti, from the mountains of 
New Mexico and about San Francisco. 
Old plants form dense rounded masses 
of more than a foot across, and com- 
posed of separate fleshy heads 2 to 3 
inches high and 2 inches thick, such 
masses sometimes containing over 200 
heads, as in the garden of M. De Laet 
at Antwerp . While in bloom from May 
to July, such old plants are very beauti- 
ful, the flowers reddish-green without 
and dark red within, paling to yellow 
at the base. They are about 2 inches 
