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ON THE HABITAT, ETC., OF CERTAIN SPECIES OF CLAUSILIA 

 FROM THE COAST OF SYRIA. 



By the Rev. A. H. Cooke, M.A., F.Z.S. 



Ecad Vlth March, 1909. 



A KECENT visit to the Syrian coast enabled me to continue certain 

 observations on the habitat, etc., of Clausilia, which I began in 

 Dalmatia and Bosnia last April. I had the opportunity of observing 

 Clausilia along about 60 miles of the Syrian coast, from a point about 

 10 miles north of Beirut, as far south as Tyre. In the neighbourhood 

 of the coast itself the land is fairly flat and unpromising, but in many 

 places the foothills of the Lebanon abut on the sea, and here Clausilia 

 abounds, the rock being limestone. 



The best place for observation is the Nahr el Kelb, or Dog River, 

 about 7 miles north of Beirut, where a small river runs into the sea 

 between precipitous limestone cliffs. At my first visit I could almost 

 believe myself back at the beautiful outlet of the Cetina at Almissa. 

 JS^ot only was the scenery strikingly similar, but on the limestone 

 slabs at the foot of the cliffs the bluey- white shells of CI. Boissieri, 

 Charp., conspicuous and abundant, corresponded exactly to those of 

 Almissana, Kiist. The species was not, it is true, so remarkably 

 confined to the moist slabs as was Almissana, being found on the bare 

 cliff face as well, but wherever there was a trickle of water from 

 above there was plenty of Boissieri feeding on the microscopic algpe. 

 It is a singularly shade-loving species, and appears to occur onlj- on 

 the southern or shady bank of the river, never in closely associated 

 groups, although so numerous, but dotted singly over the cliff face. 



Associated with Boissieri, but much fewer in number, was 

 CI. strangidata, Fer. This is a species which, exactly like alhocincta, 

 Pfr., of Brenj, loves to feed on the surface of clay, and Avherever 

 a clay band occurs in the limestone of the Nahr el Kelb it is certain 

 to be found, its beautifully laced shell often daubed and disfigured by 

 the mud. Green food is near it, but its tastes apparently do not lie in 

 that direction. 



On looking over my specimens of these two species a few shells occur 

 which I am quite unable to assign definitely to one species or the 

 other, and yet I am sure they do not belong to a third. Considering 

 how numerous in individuals both species arc, innocent errors must 

 occasionally occur, and it seems probable that in these apparent 

 hybrids we have the descendants of these mixed marriages. 



Living close by Boissieri and strangidata at the Nahr el Kelb, and 

 with strangidata alone at the lighthouse at Beirut, is a third species, 

 mcesla, Fer., whose habits are so singular that I would almost wager 

 that ten collectors out of twenty would fail to discover it at all. It 

 may be described as almost an underground species. The discovery 

 of one or two worn specimens at the foot of the same cliff on the face 

 of which Boissieri and strangidata were abundant and conspicuous led 



