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habit of growth of the Platycerum ivallicii fern, which is generally 

 situated on high trees, and full of rich humus. Nowhere did I come 

 across a solitary instance of natural reproduction on the ground in 

 the forests, which is attributable, I conceive, to the two following 

 causes, both of which militate against the perpetuation of this 

 tree : — (1) fire ; (2) excessive density of canopy, the latter proving 

 injurious, either from want of light, or by depriving them of 

 meteoric precipitates, e. g., rain, dew, &c. The matured specimens 

 of the Ficus elastica met with, were of a solitary habit ; groups of 

 over twos and threes seldom occurring, and these without exception 

 had originated in one of the above ways. The difference in habit 

 of growth between the aerial roots and branches were sufficiently 

 marked to admit of the exact height from the ground being fixed, at 

 which the descent of the former commenced; and among the numer- 

 ous measurements taken, the maximum distance was ascertained to 

 be forty-seven feet, and the minimum sixteen. Ultimately, the 

 tree is killed that has served as a cradle in infancy and a support 

 in later years to this epiphyte, and, by a process of inosculation, 

 the aerial roots unite, forming into one massive furrowed trunk, 

 for which these trees are conspicuous. The lateral branches, how- 

 ever, continue to develop numerous abnormal roots, which ulti- 

 mately reach the ground and become subterranean, when they 

 serve the double office of props to the wide-spreading limbs, — which 

 appear too heavy to support their own weight, — and organs of 

 absorption. This is the natural habit of the Ficus elastica as is 

 met with in its natural home. The plantation at Magayee, which 

 forms part of the gwasz-evergreen belt that marks the change in 

 vegetation between the plains and hills, situated within three miles 

 of the railway, and sixty miles from Rangoon, is the locality that has 

 been selected as the site to start this new branch of arboriculture. 

 Here the humidity of the atmosphere and physical conditions of 

 the soil, including light, shade, humidity, and drainage corre- 

 spond nearest to the habitat of the tree, while the difference in 

 the chemical composition of the soils is, I am inclined to think, of 

 secondary importance in tree growth, provided a good loamy soil of 

 sufficient depth can be substituted — one in which the admixture of 

 clay and sand are, in such proportions, as to ensure the loose and 

 porous qualities of the one being corrected by the plastic and re- 

 tentive qualities of the other : a proponderance of sand or gravel, 

 however, should be avoided, and drainage carefully attended 

 to. Men who have devoted time and thought to this subject, do 

 not attach the same importance to the chemical properties of a soil 

 for arboriculture, as they do for agriculture, on the score that the 

 leaves of trees return to the earth, the mineral food absorbed by them. 



