108 | THE ORCHID REVIEW. 
off by the decaying leaves may benefit the plants, as well as the utility 
of damping down occasionally with manure water, or the use of lime ce 
soot to generate ammonia, when growth is active. As already remarked, 
the development of aerial roots by the plant is a provision for obtaining the 
necessary food from the air, instead of from the soil, and cultural conditions 
have to be modified accordingly. In fact we have long ago discovered that 
epiphytes have to be treated with some regard to their peculiar nature. 
These various facts, I think, will show the utility of a knowledge of the 
conditions under which any plant grows in a wild state, and the importance 
of imitating them in their essential character. Many intelligent cultivators 
recognise this—in fact the late Mr. John Day is said to have travelled with 
the express object of observing some of the conditions under which Orchids 
grow in their native homes—and some of those who boast of the superior 
value of what they call practical knowledge are all the time imitating certain 
of the very conditions, a knowledge of which they profess to. consider as of.-4 
such little importance. The fact is the success with which many Orchids 
are cultivated at the present day is largely due to an intelligent application 
of the hints which have been supplied by collectors and travellers as to how 
and where these plants grow in a wild state. It is not the slavish copying 
of every trivial condition, many of which are purely accidental and non- 
essential, but a knowledge of what conditions are essential, and how to 
apply them or modify them to suit the artificial conditions under which they 
are grown in our houses, that is the important matter. I have heard it 
remarked that this is all very well in some cases, but there are Orchids 
which will grow best in houses or under conditions which theoretically they 
ought not to. This, however, I do not believe, and consider that such cases 
only prove our theories to be erroneous, or more correctly our knowledge to 
be imperfect. A few Orchids may be more luxuriant under cultivation than 
usually seen in a wild state, but this is due to a superabundant food supply, 
and the unremitting care bestowed on them by the cultivator—in short, to 
protection from the struggle for existence. 
Lastly may be considered how these questions affect the Orchid collector. 
Complaints are sometimes made that collectors of new Orchids seldom 
furnish any information which is of the slightest use to the cultivator, and 
these complaints are not made without good reason. In some cases collectors 
themselves know very little, as they often buy the plants of the natives, with- 
out seeing them growing, and when they could impart useful information they 
often withhold it for fear some rival may use it to his own advantage. But I 
think every necessary item of information, such as h 
