96 Journal of the Asiatic Society of Benga’. [N.S., XIX, 
the rainfall falls below 36 inches the ‘‘ Kyatti-myve”’ type of 
soil develops and the Thorn Forest passes to the Acacia catechu 
Thorn scrub. This covers large areas from Thavetmyo to 
Minhla On the clays of the Minbu and oe anti- 
clines it is replaced by the Euphorbia semi-deser 
Much of the chaung-alluvium and hill- on. is cultivated, 
but where level tracts have been left they become covere 
with Zizyphus Thorn scrub, relieved near chaungs by the 
rene ah hedgerow assemblage. 
alluvial sandbanks are the home of the Kaing grass, 
but ibe sgcemebinn: must be regarded entirely as a seral or non- 
climax community. In time trees will appear and the land 
will become covered with forest. 
The important points to notice are that entirely different 
types of vegetation occur on different soils under the same 
climatic conditions whereas the same type of vegetation (e.g. 
Acacia Thorn scrub) occurs on entirely different soils under 
different climate conditions. In short climate and soil in Cen- 
tral Burma to a considerable extent counteract one another. 
IV. Description oF THE PLANT Formatvions:! 
MONSOON FORESTS. 
i. Tectona grandis Forest (Teak Forest). Tectona gran- 
dis hyiion. ‘Teak locally forms pure forests and thrives on a 
light, well-drained soil. Where the svil is somewhat heavy, 
the presence of lime is very beneficial. The stunted Teak- 
Forests studied by the writers near Allanmyo and Thayetmyo 
e 
2. cme and Dipterocarpus Forests (Ingyin Forest and 
Eng Pecekes or Indaing). Pentaeme-Dipterocarpus hylion. The 
most abundant trees in these forests are Eng (Dipterocarpus 
tuberculatus Roxb.) and Ingvin (Pentacme suavis A. DC). 
may occur separately (as ‘ oe ) or together — 
ciations). Other common trees are Terminalia tomentosa W. 
(Taukkvan) Nylia dolabr sisetans Benth. (Pyinkado), Shires 
obtusa Wall. (Thitya) Aporosa macrophylla Muell. (Ing yin) 
and Diospyros birmanica Kurz (Té). The principal, sometimes 
the only undergrowth of the Indaing is grass—Andropogum 
cortortus Linn. or A apicus Trin. in the north and Pollinia 
articulata Trin. in the damper regions of the south (e.g. north- 
east of Prome). On certain areas of eevee the trees become 
_— 
ll 
fa) 
<4 
i Us the nomenclature ae by F. E. Clements, Plant 
incasekan eCaPnibe e Inst., Washington, 1916. 
