300 
LIST OF WORKS, ETC. 
tion of these animals, especially in South America, says the 
terrestrial Pulmonobranchiata are much more abundant in the 
warmer regions of the different quarters of the globe than in 
the more temperate parts, while the aquatic species are more 
abundant in the latter than in the former. 
He observes that the terrestrial species gradually diminish 
in number as we proceed from the warmer regions towards the 
pole ; and as we ascend from the plains to the tops of moun- 
tains. Out of the 156 species which he found in South 
America, 137 were found between the 11th and 28th, 28 be- 
tween the 28th and 34th, and only 13 between the 34th and 
45th degrees of south latitude; and 126 species were found 
under 5000 feet, while only 4 were found above 5000 feet and 
below 11,000 feet, and 6 at more than 11,000 feet above the 
level of the sea. 
V. 
LIST or WORKS AND PAPERS ON BRITISH LAND AND PRESH-^ 
WATER MOLLUSCA. 
Joshua Alder. Hotes on the Land and Fresh- water Mollusca 
of Great Britain, with a revised List of Species. Mag, 
Zool. and Botany^ ii. 101. (Aug. 1837.) 
George J, Almann. Description of a Hew Genus of Pulmo- 
nary Gasteropods, Geomalacus. Ann, and Mag, N, H, 
xvii. 297. 1846. 
Ch, Asheord. List of Land and Fresh-water Mollusca of 
Ankworth, Yorkshire. Zool, xi. 481. 1854. 
Description of a new British Limnea. Ann. and Mag. N. 
H. xvii. 396. 1846. 
W. Baird. Long suspended Vitality of a Snail. Ann. and 
Mag. N. H. vi. 68. 
W, Baker. A Shower of Snails. Zool. ix. 3187. 1851. 
