58 Journal of the Asiatic Society of Bengal. (January, 1913. 
IntRoDUCTORY NOTE. 
The sponges of the Lake of Tiberias are of considerable 
interest. They fall naturally into two groups, one of which is 
represented by a race of the widely distributed Ephydatia flu- 
viatilis, while the other consists of four species confined, so far 
as we know, to the lake and its immediate vicinity. The latter 
group includes representatives of two genera that seem to claim 
recognition as new, although I have been acquainted for some 
years with forms belonging to one of them. 
ollowing is a list of the species obtained :— 
1. Ephydatia fluviatilis syriaca, Topsent. 
2. Nudospongilla reversa, gen. et sp. nov. 
3. N. mappa, sp. nov. 
4. N. aster, sp. nov. 
5. Cortispongilla barroisi (Topsent), gen. nov. 
perhaps not really allied to the Potamolepidinae, but liable to 
be confused with genera included among them. 
paper. The following key may be useful to naturalists who 
visit the lake :— 
Key to the Sponges of Lake Tiberias. 
1. Sponge soft, by no means to : 
gemmules present if conditions are 
smooth; birotulate gemmule-spi- 
cules as a rule more than 0-03 mm 
long) : : .. Ephydatia fluviatilis 
J . 59). 
2. Sponge hard; no gemmules. ple Bah 
