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aberrations caa be explained more or less easily ; practically, they will remain a source of 

 difficulty to those who are uot botanists. 



However, there are certain indications, derived from the conditions of soil, and especially 

 of the substratum, and from the physical nature of the locality, by which (guided by certain 

 characteristic plants) one can finally reduce such doubtful jungle formations to their proper 

 places more or less accurately. Let me give an example. The savannah mixed forests of the deep 

 alluvium of the Irrawaddi plains are very easily recognised in their normal state, but when 

 the trees in them get crowded, as along the cart road from Tharawa (opposite Henzada) 

 to Thabyaygon on the Hline river, they become composed of so many trees, derived from the 

 lower mixed forests, as to make it difficult to say whether we have to do with a savannah or 

 lower mixed forest. In this case the conditions of soil and climate are the same, but the allu- 

 vium is probably not deep enough to produce a vegetation identical with that which we might 

 have expected here. Possibly also a different substratum exists. The general growth, how- 

 ever, of the trees, and especially the long coarse wild sugarcane so characteristic of savannah 

 forests, are indications strong enough to place the present forest in the same division with 

 savannah mixed forests, or to make a slight variety of it. 



The vegetation of cultivated lands, swamps, waters, &o., is of course of little or no 

 value to forest officers, but I allude to it here for the sake of completeness. 



7. Enumeration of the different kinds afforests, Sfc, and their botanical characters. 



Having shewn in the preceding section how I distinguish the larger divisions of 

 vegetation, in Pegu, it remains for me to classify the different smaller variations of vegetative 

 combinations, as the different kinds of forests, savannahs, &c., are called by phytogeographists. 



I shall first submit a conspectus of them, and afterwards treat them one by one in the same 

 order as here indicated. 1 find some little difficulty in treating the same kind of forest under 

 one and the same heading, because, although practically identical, the same kind of forest 

 contains often an admixture of trees peculiar to the zone in which they grow. In such 

 cases I have usually added some of the more striking peculiarities in the different zones. 

 Some of the forests occur only in one single zone, such as the Sha forests in the Prome 

 zone. 



It was my intention to omit in the present scheme of forests, &o., all those forests which 

 are met with East of the Sittang, and to restrict myself solely to the vegetation between the 

 Irrawaddi and Sittang rivers. I should have done so for two reasons, viz., (I) because I un- 

 derstood from the official correspondence before me, that the area should be limited to that extent, 

 and, (2) because a due appreciation of the character of the Karen or Martabau hills (as I 

 have ventured to call the whole range of hills between the Sittang and Salween rivers) can 

 only be attained from a longer residence in those regions. I myself have travelled but little 

 in those parts, and I spent hardly more than two weeks in exploring the interior portions up 

 to 7000 feet elevation. After reconsideration, however, I thought it might be useful, in spite 

 of the incompleteness of my experience, to introduce those forests. These are all high level 

 forests, viz. the evergreen hill forests and the hill Eng forests. 



I. ORIGINAL VEGETATION. 

 A. Forests. 



AA. EvEKGREEN FoRESTS. 



1. Littoral forests. 



a. Mangrove jungles. 



b. Tidal forests. 



2. Swamp forests. 



3. Tropical forests. 



a. Closed tropical forests. 



b. Open tropical forests, or moist forests. 



4. Evergreen hill forests, or temperate forests. (All unrepresented in the Pegu Tomah). 



a. Drier hill forests (3000-7000 feet). 



b. Pine forests (3000-7000 feet). 



c. Damp hUl forests (3000-6000 feet). 



BB. Deciduous Forests. 



5. Open forests (chiefly on diluvial formations). 



a. Hill Eng forests (not represented in Pegu). 



b. Eng or laterite forests. 



c. Low forests. 



