EUCALYPTUS TREES. 613 
veloped into the most picturesque magnificence, into 
the most grateful yield, into the most bloomy feat- 
ures, and, above all, into the most extensive instruct- 
iveness. Many horticulturists of eminence have 
shown already that, for impressive groups of plants, 
even in colder countries, we can dispense with sub- 
tropic forms, although, for half the year, they may 
still more embellish the vivid and graphic effect by 
~ bringing Tree-ferns, Palms, Yuccas, Melianthus, Bam- 
boos, Agaves, Fourcroyas, Cycadee, Papyrus, tall Gah- 
nias, Cardylines, Cannas, Richardia, Acanthus, and 
the great Mexican Composites (Ferdinanda and Mon- 
tagnea ), and other spacious or conspicuous, and not 
absolutely tender plants, from conservatories, there 
to the open ground, with a view of enhancing the 
effects of such groups as may permanently be con- 
stituted by the hardy Pines, Ailanthus, Gynerium, 
Heracleum, Ferula, Donax, and even ordinary Arti- 
chokes and Helianthus; or the sown Ricinus, Sorg- 
hum, and Maize; or the nobler species of Rheum, 
Polygonum, Gunnera, or the tall Kamtchatka Angeli- 
ea, all available, even in colder zones, for unprotected 
garden-spots. 
But what shall I say of our operations here and our 
facilities in this respect, when the larger share of 
Middle European conservatory plants, from a Norfolk 
Island Pine to an infinite number of other plants, can 
_ be trusted out by us at once under a genial sky into 
the open air? How would such facilities be turned 
to account by eminent horticulturists of scientific 
knowledge and refined taste if in Middle Europe the 
clime allowed of it! In this respect a botanic garden 
can fulfill also here its duty, by introduving the nobler 
