530 MR. H. B. TRISTRAM ON THE TERRESTRIAL [June 27, 
7. ReEPorT ON THE TERRESTRIAL AND FLUuvIATILE MOLLUSsCA 
OF Patestine. By H. B. Tristram, Corr. Mems. 
The character of the Molluscan fauna of Palestine partakes, as 
might have been expected, of the same variety which marks the other 
branches of its fauna and flora. There are, however, fewer exceptions 
to its general character as a part of the Mediterranean basin, and 
fewer traces of the admixture of African and Indian forms. Northern 
types, especially of the genus Clausilia, are frequent in the Lebanon 
and on its southern spurs in Galilee. The Molluscan fauna of the 
maritime plains and the coast posesses no features distinct from those 
of Lower Egypt and Asia Minor The shells of the central region 
are scarce and not generally interesting ; while on the borders of the 
Jordan valley and in the southern wilderness we meet with very di- 
stinct groups of Helix and of Bulimus, chiefly of species peculiar, or 
common in some few cases to the Arabian desert. 
The fluviatile Mollusca are of a type very much more tropical in 
its character than that of the terrestrial shells. There are here but 
few species similar to those of the east of Europe. Most of the spe- 
cies are identical with, or similar to, those of the Nile and of the 
Euphrates ; and some ‘of the genus Melanopsis are peculiar to the 
Jordan or its feeders. It seems probable that the inhabitants of the 
waters were better able to sustain the cold of the glacial epoch than 
the mollusks of the land; and from the post-tertiary remains found 
by the Dead Sea we may infer that the species now existing have 
been transmitted from a period antecedent to the glacial ; while the 
more boreal forms introduced at that epoch have maintained their 
existence in the colder districts of Northern Palestine to the exclu- 
sion of the southern species, which have not succeeded in re-esta- 
blishing themselves. The beautiful group Achatina, requiring a de- 
gree of moisture not generally found in Palestine, is only represented 
by a few insignificant and almost microscopic species. 
The Molluscan fauna of this country has been less neglected that 
other branches of its natural history. Olivier first published a few 
species through Férussac in 1821. Ehrenberg added many more, 
of which eighteen were described as new. Boissier published his 
list in the ‘ Zeitschrift fiir Malakologie’ in 1847. Bourguinat pub- 
lished and figured in 1853 the collection made by M. de Sauley; and 
Dr. Roth, in his ‘ Molluscorum Species,’ in his ‘ Spicilegium Mol- 
luscorum,’ 1855, and ‘ Coquilles Terrestres et Fluviatiles,’ edited by 
A. Mousson, 1861, has supplied us with a catalogue far more com- 
plete and exhaustive than any of his predecessors. 
It will be seen that while we have not, as the result of our 
expedition last year, to report many entirely new species, we suc- 
ceeded in obtaining very many which had not occurred to Dr. 
Roth, and several which had escaped the observation of all our 
predecessors. 
As it seems probable that several species have been redescribed by 
authors who were not acquainted with the works of previous writers, 
I have thought it advisable to confine my report to the Zoological 
