32 BOTANY OF BIHAR AND ORISSA. 



*** ■* ' ;' ltion of man (cp. para. 98) 



important (see para. 103). 



With such an immensely old land surface as that of the I 

 Peninsula, with the majority of the species probably immensely old, 

 arni with no serious obstacles to their distribution," their occurrence 



ot similar climate and soil. And by climate must here lie included 

 the very local climatic conditions of environment due to the position 

 of a plant in a valley in contrast to one on a hill, or in the shade of 

 other trees, as compared to one in the open. As insolation is an 

 essential factor ei climate, the local climate in the shade of a mango 

 tnp is radically dii uide. And thus 



a plant species found in the open in the humid climate of Purneah 

 ma\ not he found m the Central tract, but nun ivcur on the moun- 

 tains of the Sod haps partial shade, or it may 

 instances. But although man; species thus find approximates 

 -opaiand iMii. t-, and the isohvetal 

 lines which, run u f Northern Champaran, 

 cab, leave our province and curve round 

 through Bengal, ,, f the Southern 



plant community is found to differ. 

 are found in many different plant 



'<,„.- -Speaking generally the effect 



uel for the flai 



repeatedly killing off young growth of all kinds 



ble to strong growing grass, s win. h 



of green material in the undergrowth as well as 



e-hardy. Symploc 



I gradually spr. , (if ' a dunip 



