1921.] The Highth Indian Science Congress. elxxxili 
from about 2,500 ft. in the Ganges wg at Hardwar to peaks above 
23,000 ft. on the Thibetan border. The Ganges and Jamna rivers 
uth he 
p ainfal e 
anges, and on the outer faces of the high ranges; north-facing slopes, 
valleys and A flanks of the intervening ranges receive much less rain, 
n places arid Snow falls down to about 5,000 ft., and frosts occur 
= about 4,000 in 
S paper Bac on observ Aap made on a trip to the gett 
of — ‘Gar nges a g the summer of 1920, supplemented by e ended 
observations about ge aan Naini Tal, and back to the vos in 
Kum 
Forest TYPEs. 
The climax ve tea ee oma Tehri Garhwal State is forest. 
There are several types of forest, depending on humidity (rainfall, expo- 
sure to insola slons and drainage) and temperature (due to altitude, 
latitude, insolation, and topogr aphy ). 
nsoon forest formations: climate sub-tropical, markedly peri- 
odic, with hakey summer monsoon. 
: of tall gomeg nang ,000 ft., on the tera 
2. ee Forests 1 ae. ,500 ft. on the bhabar hes « e a direct 
osm the > Himalay an forests, but lie seeds the area 
Cy 
¢ 
5 
~ 
cadet sidet 
Shores robusta forest, 1 ,500-2,500 ft., Pe the outer slopes and to 
very limited extent up valleys. The fina 1 forest is an almost 
oon dence stand o f Shore rea ro 
Pioneer forests contain Mallotus philippinensis, Anogeis. 
iatifoia, urraya koenigii, Cassia fistula, Trewta audi 
alis 
us forests, : 2,000-5,001 ft., below severe 
frost, and now, i wate and relatively humid ‘locations ; ex- 
tends far up river valleys, and up ~_ tected ravines, Domi- 
nated by Bauhinia variegata, B. retusa cue vahlii, » Grewia 
q 
os 
ue) 
® 
rt 
B 
a8 
gf 
4 
hebula. 
Pioneer shrubs: Huphorbia Royleana, Carissa spinarum, 
usticia adhatoda, Rhus —— an vebutnua: 
Pioneer forest : N yetanthes owed tis, 
Sapium insigne, Odina wodier, Premna latifolia, erage 
pinna 
B. Broad-leaf slerophyil formants: 4,500-11,000 ft.; climate tem- 
perate, Bes riodic, mons in summ Say eaalieiy high. 
Quorens i incana- POLST ae um forests, 4,500-8,000 
mountain crests, northern slopes, map g in pro otected avines 
na 
ceae, Cornus ca niform 
capes pioneers oa ridges and drier places) Berberia 
lye Rosa moschata. clans ger ubus 
elliptic, Crataegus crenulata, pashia, gene ar 
?inus mero — 3,500-7,000 ft., on exposed, well-drained, 
and south-f ridges, an edaphic forest in cenene too dry = 
be oce err w either the upper monsoon-deciduous or 
Quercus incana-Rhododendron arboreum forests, but <thiess 
