Bod Notes on the Indian terrestrial Gasteropoda. [No. 4, 
Notes on the distribution of Indian terrestrial Gasteropoda considered 
with reference to its leaning on the origin of species.—By W. 
THEOBALD, J7. 
«There are more things in Heaven and Harth, Horatio, than are dreamt of in 
your Philosophy.” 
I am led to make the following remarks on a subject of considerable 
interest, by some suggestions contained in a Paper by my friends the 
Messrs. Blanford, which appeared in the fourth number of the Journal 
of the Asiatic Society for 1861. This paper is I trust but one of 
many which we may receive from the same writers, and it is by such 
contributions alone that we can hope to arrive at sound and compre- 
hensive views of the distribution of the animals of which it treats, 
which, from their often limited range within the tropics, and the mark- 
ed and peculiar forms they there exhibit, afford peculiar facilities for 
estimating the amount of support, derivable from their study, which 
they afford to the ingenious theory of Mr. Darwin of the origin of 
species. In several respects indeed the problem of the distribution 
of land mollusea and the origin of both their generic and specific 
types, is less encumbered with subsidiary considerations, requiring 
special allowance and elimination, than the same problem as regard 
any class of the vertebrata, and the land mollusea therefore afford not 
only a simpler, but also a more satisfactory field for testing how far 
a theory, which may find plausible justification and analogical support 
from admitted physiological modifications among the vertebrata, is 
applicable to and in aecord with our knowledge of the invertebrate 
classes. 
With this view therefore it will be well to sift carefully a sugees- 
tion made in the above quoted paper, which does not appear to me 
to stand on any firmer foundation than mere hypothesis. 
After tabulating the distribution of the Terrestrial Gasteropoda of - 
the Kolamully, Putchamully, Kalryenmully and Shevroy ranges of 
hills, the authors arrive at the conclusion that the whole area is 
occupied by one and the same fauna, (referring of course to the mol- 
lusca only,) with which conclusion I fully agree, but this uniformity 
is brought about not by the dispersion of the same species over the 
entire area, but by the occurrence of the same species on ranges of 
