FORBES ON THE SMYRNA FOSSILS. 163 



One belongs to the genus Melania, and appears to be a new- 

 form. 



On the whole, the evidence afforded by the fossils tends to show 

 that the great fresh-water formation which skirts the Gulf of 

 Smyrna and the coasts of many islands in the neighbouring por- 

 tion of the Archipelago is of the age of the Paris basin and London 

 clay. Whether the fresh-water tertiary basins of the interior of 

 Asia Minor and of the valley of the Xanthus, and the islands of 

 Cos and Rhodes, are of the same age, is very doubtful. Judging 

 from the numerous fossils collected by Mr. Spratt and myself in 

 those tertiaries, I am inclined to pronounce them of a different 

 age and of later origin ; anterior, however, to the pliocene marine 

 formations of Asia Minor and the Sporades. 



I may add that Mr. Strickland, in his Memoir on the Geology 

 of Smyrna, mentions a Unio, a Cyclas, a Helix, and a Cypris in 

 the tertiaries of Bournabat which have not been met with by 

 Lieutenant Spratt. 



Impressions of the leaves of vegetables, too imperfect for deter- 

 mination, accompany the specimens laid before the Society. 



List of the Fossils. 



a. Planorbis Spratti E. Forbes. 



b. Paludina Stricklandiana E. Forbes. 



c. Melania Hamiltoniana E. Forbes. 



1. Limneus longiscatus Brongniart. 



Many casts, not distinguishable from French and English examples. 



2. Limneus ventricosus Brongniart ? 



The specimens closely resemble the recent L. auricularius. The spire 

 appears rather shorter that it is represented in the figures of the French 

 fossil, to which I have referred it. 



3. Planorbis rotundatus Brong. 



Such specimens as retain the shell exhibit transverse sulcations of growth. 



4. Planorbis cornu Brong. ? 



Specimens with the shell are spirally striated, like the recent Planorbis 

 similis. Not having compared it with authentic French examples, I have 

 marked this species with a query, though it closely agrees with the figures. 



5. Planorbis prevostinus Brong. ? 



Too imperfect a specimen for certain identification. 



6. Planorbis planulatus Desh. ? 



The inner whorls do not occupy so much space as they are represented 

 to do in the French figures. It is closely allied to the recent Planorbis 

 nitidus. 



7. Planorbis Spratti, nov. sp. (woodcut, Jig. a). 



M 2 



