FAUNA AND FLORA, RATBURI, PETCHABURI. 138 
on the boundary in N. Lat 12° 54’, and asarule in that district the 
boundary is over 1100 metres in height, rarely fajling below 800 
metres. There is an entire absence of plateau-like or undulating 
ground, the mountains being steep sided, and the ridges or summits, 
seldom more than 10 to 30 metres in breadth, falling away on either 
side to the valleys at slopes varying from 25 to 60 degrees. Generally 
speaking the summits of ranges or ridges are from 300 to 500 metres 
higher than the valleys directly beneath them. 
There is, thus, very little deep humus or water holding soil, 
the greater part of the rainfall finding its way immediately to the 
rivers, and accounting for the sudden floods to which these streams are 
subject, it being no uncommon occurence for the Petchaburi river in 
the rainy season to rise 20 feet in 12 hours, and 30 feet has been known 
in the same period. The formation is granite with a few small and 
isolated limestone outcrops. 
With the exception of H. odorata, which is mainly confined to 
the banks of running streams, and a species of Salix growing both on 
the banks and in the shallows, the jungle is very varied, but the 
greater portion is dark and gloomy—the undergrowth varying in 
intensity according as the overhead foliage is light or heavy. Once off 
the main game tracks it is usually necessary to cut one’s way 
when ascending to mountain tops for work. As previously 
stated, the ridges slope away sharply on either side of the crest, but 
no view is obtainable until extensive clearing has been done. In the 
same way in the valleys, if one required sunlight in camp to dry 
clothes or dry up the land leeches, it was always necessary to spend 
some hours felling the timber and jungle, and then frequently, owing 
to the depth of the ravine, it was only possible to obtain 3 or 4 hours 
sunshine, 
The Karangs make a few paths in the vicinity of their houses 
and clearings, but otherwise the only paths available are those made by 
the wild elephants. ‘These cross and recross the streams every 50 or 
100 yards but are otherwise frequently quite good. A few main tracks 
were found leading over the less steep ranges—paths used by the ele- 
phants during the rains when in search of bamboo shoots, and leading 
over dividing ranges from one valley to another. 
I propose to describe a couple of trips in that country which 
will indicate its nature away from the main stream. 
