are each adapted to distinct conditions of life, and our failure arises 
from our mistaking a general principle for an universal law. If a 
great majority of Epiphytal Orchidee swarms in damp tropical 
forests, there is a considerable minority which lives in an entirely 
different climate, of which a few examples will not be without 
instruction. Thus in the genus Oncidium itself, where almost all the 
species are of tropical habits, O. nubigenum is only found on the 
cool mountains of Peru, at the height of 14,000 feet; it will there- 
fore require a treatment altogether distinct from that of the mass 
of the genus Dendrobium moniliforme and catenatum, again, occur 
onlyin Japan, as far north as 37° or 38°, or the parallel of Lisbon, 
and are periodically subject to a very low temperature. 
But the most remarkable instances of a disposition on the part 
of some Orchideous Epiphytes to depart from the ordinary habits of 
the tribe are found in Australia and its dependency New Zealand. 
In some extremely valuable observations upon the geographical dis- 
tribution of the Orchideous plants of New Holland, which have been 
placed in our hands by Mr. Allan Cunningham, we find a passage 
which bears so Fig upon this subject, that we cannot do better 
than quote it entire. ; 
““ There are two, if not three plants of this family,” says this 
enterprising and scientific traveller, ““ that grow on trees or rocks. in 
New South Wales, whose natural constitution should, in eultivating 
them, form exceptions to the uniformly adopted mode of treatment of 
Epiphytes generally in our English stoves ; namely, that in which 
high temperature and considerable humidity are employed. These 
are Dend. emulum, Br., an Epiphyte uniformly found upon the 
rugged trunk of Eucalyptus resinifera or Ironbark, in the open very 
dry forest grounds of the older colony at Port Jackson ;—Cymbi- 
dium canaliculatum, Br., which of late years has been observed 
beyond the Tropic, both at Moreton Bay and still farther to the 
southward at Hunters River, growing upon the principal limbs of 
several of the Eucalypti in the dry open shadeless forest. These two 
Epiphytes flourish most luxuriantly in an extremely dry atmosphere, 
and flower usually in the summer season in their native wilds, the 
high temperature of which is oftentimes greatly inereased by the 
blighting hot winds; which not unfreguently prevail at that period 
from the north-west. The third is Dendrobium undulatum of Mr. 
Brown, a handsome species, originally discovered by Sir Joseph 
Banks at Bustard Bay, and which has been lately found on bar- 
ren hills, naturally clear of timber, upon the banks of the Bris- 
bane River at Moreton Bay, where the plant forms tufts on bare 
rocks exposed to the full heat of the sun, which during nine months 
of the year is very considerable on that part of the coast. These 
e were some years since received alive at Kew, from New 
outh Wales; and with them was communicated, as a guide to 
their culture, a note of the partieular situations, with rd to expo” 
sure to drought, &c. which they naturally occupy and delight in, in 
their native wilds. These particulars were, however, in all probability 
wholly unheeded in the King's Gardens—the plants were 2580 
