331 
Extracts from the private Letters of Dr. J. D. Hooker, written during 
Botanical Mission to INDIA. 
(Continued from p. 308.) 
CALCUTTA TO DARJEELING IN SIKKIM-HIMALAYA. 
From Silligoree a sudden descent leads to the Mahanuddy river, 
here flowing S.W., in a shallow valley, over a gravelly bottom of small 
schist and slate pebbles. It is a bustling river, even at this season ; its 
banks fringed with ras and as clear and sparkling as a trouting 
stream in Scotlan it, the Terai commences at once; the 
road ascends a little, vinding iaa a thick brush-wood, choked. with 
long grasses (Sacchara, &c.) and Cyperacee, and but few trees, chiefly of 
Dalbergia Sissoo, and a Bue fruited Sterculia. The soil is a red, 
friable clay and gravel, very ochreous; the gravel is all of quartz or 
mica and felspar pebbles, with scattered flakes of mica and occasionally 
grains of hornblende and perhaps felspar, the decomposition of which 
produces the clayey matrix. 
sweet-scented ciii l, and ially a beautiful small 
rcuma, were in the greatest profusion Leaves of terrestrial s 
too, appeared, with Ferns (chiefly ) ipe , some Side, an 
very gentle slope, towards the foot of the hills. The beds, some dry, 
of many small streams, are crossed, all very tortuous, and invariably 
flowing in an easterly and westerly direction, instead of following a 
straight course from the mountains. Their banks are richly clothed 
with brush-wood and climbers of many Orders, such as Convoleuli, 
Hiraea, Leea, Vitis, Menispermum, Oucurbitacee, and Bignoniacee. The 
transverse course of these streams seems to indicate a slope towards the 
hills. Their pent-up waters, percolating the gravelly clay bed, and partly 
carried off by evaporation through the stratum of ever-increasing 
vegetable mould, must be one main agent in the production of the 
malarious vapours of this pestilential region. Add to this, the deten- 
