544 MR. TRISTRAM ON THE MOLLUSCA OF PALESTINE. [June 27, 
115. Unto micnonti, Bourg. 
In the Zerka or Crocodile River. Figured by Bourguinat from 
the neighbouring streams of Jaffa. Appears to be but a variety of 
the U. marginalis, Lamarck, a variable species found in India, Mau- 
ritius, and China. 
116. Unto sauucyt, Bourg. 
From the Kishon. Found by M. de Saulcy in the streams near 
Jaffa. This species is very like U. mosalensis, Lea, from the Tigris, 
if indeed it be not the same species. 
117. Unto stmonis, n. sp. 
T. ovato-rotundata, supra arcuata, infra subrecte arcuata, antice 
posticeque rotundata, ventricosa, crassissima, concentrice 
striata, epidermide nigra vel nigrescente, vel in juvenibus fusco- 
virescente ; umbonibus valde prominentibus, recurvis, extremi- 
tate anteriore approximatis, striis undulantibus sculptis ; dente 
cardinali crasso, altissimo, denticulato, sulcis rigidis impresso ; 
dente laterali crasso, producto; sinu pallial profunde impresso ; 
t. infra nacreo-roseo pulcherrime resplendente. 
Long. 66, lat. 44, diam. 32 mill. 
This shell is found in the Jordan, the Sea of Galilee (where it 
reaches its greatest dimensions), the Orontes, and the Leontes (Lita- 
ny). Its rotundity, thickness, solidity, and the brilliant rosy tint 
of its nacreous interior distinguish it at once from every other spe- 
cies. The massive solidity of the young shells is very remarkable. 
The rosy tint is equally brilliant in all the specimens I have seen. 
118. UNio EPISCOPALIS, 0. sp. 
T. elongato-ovalis, valde inequilateralis, subcomplanata, crassa, 
supra recta, infra compressa, postice rotundata, antice elon- 
gata, concentrice striata; epidermide nigerrima ; umbonibus 
prominulis ; dente cardinali alto, crasso, subacuto, fortissimo, 
laterali forti, elongato, nacreo, purpureo-episcopali pulcher- 
rimo; sinu palliali profundissime impresso. 
Long. 98, lat. 56, diam. 35 mill. 
This, the prince of Oriental Unionidae, is not uncommon in the 
Orontes. I found a dead valve by the Leontes, but did not meet 
with it in the Lake of Galilee. From its brilliant purple hue, which 
is preserved in the most worn valves, from its size, its jet-black epi- 
dermis, and the peculiar compression, it is a remarkable and isolated 
species. I can find no Unio in the collection of Mr. Cuming which 
at all resembles it. 
119. Unio rripouiranus, Bourg. 
Near Tripoli. 
The following is a list of species mentioned by previous writers, 
but not found or identified by us; many of them are doubtful :— 
