Dec. 1915. ZOO-GEOGRAPHICAL DIVISIONS FOR SIAM. 251 
plains—we generally finda change in the fauna also, and this is 
particularly notable in a contrast between the life of the two latter 
kinds, and is perhaps always best illustrated by the mammals. Siam 
shows some of these orographical and vegetational differences, and it is 
in accordance with them that I have attempted to distinguish a 
number of divisions, about which, however, it is quite impossible to 
draw sharp boundaries. 
Northern Siam, as I have defined it is, on the whole, a moun- 
tainous area, and Western Siam is the same. Hastern Siam is, 
speaking broadly, a sub-montane division of a different formation 
from the rest of the country, and with a different vegetation. In 
Central Siam I have endeavoured to include the whole riverine plain, 
and that only. South-eastern Siam contains both mountains and coastal 
lowlands ; as does Peninsular Siam, which, from the present point of 
view, forms naturally a geographical sub-division. I have considered 
it here, as starting from the gap in the mountains between Koh Lak 
and Tenasserim, though it might with equal propriety be regarded as 
commencing at Muang Kra or Pakchan. Though I should have pre- 
ferred, with the classical instance of Egypt as precedent, to have 
divided the Menam country into Upper and Lower. Siam, I have (in 
deference to the wishes of several members of the society) used the 
terms Northern and Central for this area, though the latter name 
seems scarcely logical since the periphery is incomplete. The other 
titles require no explanation except that of Peninsular Siam about 
which a word or two may be said. 
American zoologists in reporting on collections from Trang, 
etc., set the fashion, and are still in the habit of referring to that area 
as Lower Siam. ‘This practice has been the cause of misunderstand- 
ing on the part of other naturalists, and has resulted in a good deal of 
confusion. For this outlying province I have, therefore, proposed the 
name of Peninsular Siam, as being especially descriptive, and, of all 
alternatives, the only one which is absolutely devoid of ambiguity ; 
which is not the case unfortunately with ‘“‘southern”—a geographical 
term of the same class as the others, and complementary to the two 
names for the river area. If collectors would refer to the above 
divisions, the stations from which their material came, a very good 
idea of the provenenance of their specimens would be obtained, even 
though the exact positions could not be located. 
