CHAP. X11. ] THE ORIENTAL REGION. 329 
adapted to local conditions to be expelled; so that it is among 
these groups alone that we find any considerable number, of what 
are probably the remains of the ancient fauna of a now sub- 
merged southern continent. 
ITI. Himalayan or Indo-Chinese Sub-region. 
This, which is probably the richest of all the sub-regions, and 
perhaps one of the richest of all tracts of equal extent on the 
face of the globe, is essentially a forest-covered, mountainous 
country, mostly within the tropics, but on its northern margin 
extending some degrees beyond it, and rising in a continuous 
mountain range till it meets and intercalates with the Man- 
churian sub-division of the Palearctic region. The peculiar 
mammalia, birds and insects of this sub-region begin to: appear 
at the very foot of the Himalayas, but Dr. Gunther has shown 
that many of the reptiles characteristic of the plains of India 
are found to a height of from 2,000 to 4,000 feet.. 
In Sikhim, which may be taken as a typical example of the 
Himalayan portion of the sub-region, it seems to extend to an 
altitude of little less than 10,000 feet, that being the limit of the 
characteristic Timaliide or babbling thrushes ; while the equally 
characteristic Pycnonotide, or bulbuls, and Treronide, or thick- 
billed fruit-pigeons, do not, according to Mr. Blanford, reach 
quite so high. We may perhaps take 9,000 feet as a good 
approximation over a large part of the Himalayan range; but 
it is evidently not possible to define the line with any great 
precision. Westward, the sub-region extends in diminishing 
breadth, till it terminates in or near Cashmere, where the fauna 
of the plains of India almost meets that of the Palearctic 
region, at a moderate elevation. Eastward, it reaches into East 
Thibet and North-west China, where Pére David has found a 
large number of the peculiar types of the Eastern Himalayas. A 
fauna, in general features identical, extends over Burmah and 
Siam to South China; mingling with the Palearctic fauna in 
the mountains south of the Yang-tse-kiang river, and with 
that of Indo-Malaya in Tenasserim, and to a lesser extent in 
Southern Siam and Cochin China. 
VoL. 1.—23 
