THE ORCHID REVIEW. 3 



"A writer once illustrated his argument by relaling that many an 

 Orchid, quite at home on the branch of a tree in its native home, will not 

 thrive in cultivation unless placed in peat and moss and in a basket 

 or pan. Why it was so he did not state, but merely gave the empirical, ' it 

 won't do.' Why does he not tell us the reason ? If he had thought the 

 matter out he would have found that the arid atmosphere of his glass- 

 house was such that it was impossible for the roots to exist, if exposed, and 

 unless covered with the peat and moss, which affords them the best imita- 

 tion possible of the condition of the air in their natural habitat. An 

 essential condition, therefore, unobserved by the operator, was present in 

 both places. ... 



"The pretty Lselia monophylla found in Jamaica has, it may be said, a 

 climate of its own, for it is only found in situations identical as regards 

 elevation, temperature, and moisture, and with the greatest similarity 

 between the humidity of the places. This plant is often described as 

 succeeding well in the Odontoglossum house, but that is exactly the 

 temperature and condition which prevails in its natural habitat. The little 

 Epidendrum serrulatum grows in coffee trees at 5,000 feet in Jamaica, and 

 is seldom found below that elevation, while in other islands, possessing a 

 greater humidity, it is found at sea level— difference of temperature 17 per 

 cent, to 25 per cent. Fahr. — difference in humidity nil. The inference is 

 clear, but nevertheless it would not do to overlook the fact that with the 

 absence of sunlight experienced in temperate climates plants require to have 

 different treatment ; but this is only an artificial condition, and does not in 

 any way affect the main argument. . . . 



" Take Broughtonia sanguinea, again, which grows and thrives well at sea 

 level, on bare trunks well exposed, in Jamaica. In Trinidad this plant utterly 

 refuses to thrive unless kept in a position the driest attainable, and even 

 it grows small by degrees and beautifully less, although the temperature 

 and position are again almost the same, but humidity differing." 



The inference which the writer draws is that humidity seems to 

 be more important than temperature, and that soil is not so impor- 

 tant as sometimes supposed; and he sums up the argument by 

 saying:— "A knowledge of the outside influences would give the 

 cultivator a much clearer hint, and put him in a more direct road, than 

 the innumerable trials he will otherwise have to make where empirical 

 methods alone are employed." Could we have a more rational argument in 

 favour of rational treatment ? 



