MALAYSIAN LAND AND FRESHWATER MOLLUSCA. 
By the Rev. J. E. Tenison-Woods, F.G.S., F.L.S., Hon. Mem. 
Roy. As. Soc. (Straits Branch). 
(Plates xxvii.-xxx.). 
Definition of the Region. — The species included in the 
following list are those indigenous to the Malay Peninsula in the 
states south of Keddah and the Indian Archipelago, exclusive of 
New Guinea. With the exception of the arbitrary line dividing 
the Malay Peninsula, the limits of this region form a province in 
natural history in the molluscan sub-kingdom. The reason for 
excluding New Guinea is that its fauna seems to belong more to 
the Pacific and Australian regions. The Philippine Islands are 
not included, because they form of themselves a peculiar province 
with very marked features, entitling them to separate considera- 
tion. 
The physical geography of the Malaysian region is another 
reason for considering its puhnonate mollusca separately. The 
region consists of an immense number of islands of varying sizes, 
from mere barren granite rocks to continental islands like Sumatra 
and Borneo. All those that are of any size are densely clothed 
with vegetation. The climate is very hot, moist, and varies but 
little. Granite is the prevailing rock, with overlying palieozoic 
strata and a few outliers of Devonian limestone. There are also 
in Borneo and Sumatra rather exten.sive developments of carbon- 
aceous sandstone and a few patches of tertiary lime.stone. The 
south-»*ast ])ortion of tlie region is made up exclusively of modern 
volcanic rocks. 
It is known that climate, vegetation, and soil have all powerful 
influences in the development of the land mollu.sca, which live on 
decayed leaves and vegetation, flourishing best amid moisture and 
