BOTANY OF THE CEYLON PATANAS. 431 
expanses in an otherwise forest-covered country ; and (ii) to what 
extent the vegetation of the patanas shows adaptations to the 
peculiar cecological factors under the influence of which it has 
been selected.” 
Owing to circumstances explained in the introduction *, the 
second part of the problem was only in part dealt with, its fuller 
treatment being reserved until an anatomical examination of 
such of the patana plants as were represented by spirit material 
could be madet. The results of that examination we now offer 
to the Society. 
The conditions of soil and climate under which these plants 
live have already been discussed in some detailt. For the 
better comprehension of facts now to be stated, a brief summary 
of these conditions may be given. The patanas fall naturally into 
two groups which, owing to differences in elevation § and their 
situation with respect to the main mountain-ridge, present marked 
variations of soil and climate. 
“Wet”? Patanas.—Above 4500 feet the rainfall is copious, and 
fairly evenly distributed throughout the year. The soil is of a 
generally uniform character. It is thus described || :—“ An 
almost pure humus, black or coloured dark brown by the ad- 
mixture of mineral substances; but apparently pebbles are 
always absent. It varies in consistency from a black mud to a 
powdery soil such as the wind will remove as dust, though this 
last condition is rarely seen, as it normally contains considerable 
quantities of water. The absence of earthworms is also remark- 
able, and is not without effect in contributing to the formation 
of a pure humus-soil. The reactions of the soil were not 
observed; attempts have, however, been made to use it for 
gardening purposes at the Hakgala Botanic Gardens, and it has 
been found to be too sour to be of any use.” 
In a soil of this character root-absorption is interfered with, 
* Pearson, Journ. Linn. Soc., Bot. xxxiv. (1899) pp. 300, 301. 
t Before the paper referred to was issued, my opportunities for carrying on 
laboratory work were so curtailed that the contemplated anatomical examination 
of my material became impracticable. My friend Mr. Parkin, who has had an 
opportunity of seeing the flora of the patanas, kindly consented to come to my 
assistance. This paper gives the result of his work, which, through the kindness 
of Professor Marshall Ward, was done in the University Botanical Laboratory, 
Cambridge.—H. H. W. Prarson. 
t Pearson, /. c. § Pearson, /. c. pp. 301, 302. | Pearson, J. c. p. 320. 
