108 



SOLLAS On the Origin of Freshwater Faunas. 



POLYZOA. 



Lagimcula repens 

 Bowerbankia densa 

 Stichoporina ? 



(Farr.) 

 (Fair.) 



LAMELLIBRANCHIATA. 



Corbicula fluminalis (Mull.) 



Cardium edule (Linn.) 

 C. edule, var. rusticum 



C. caspium (Eich.) 



C. crassum (Eich.) 



C. trigonoides (Pall.) 

 C. trigonoides, var. crassum (Grm.) 



C. pyramidatum 



C. baeri 



C. longipes 



C. barbot-de-inarnii 



C. catillus 



C. pseudocatillus 



Adacna laeviuscula 



(Grm.) 

 (Gnn.) 

 (Grm.) 

 (Grm.) 

 (Eich.) 

 (Abich.)? 

 (Eich.) 



(Pall.) 

 (Eich.) 

 (Eich.) 



A. edentula 



A. plicata 



A. vitrea 



Anadonta ponderosa 



Dreissena polymorpha (Ben.) 



D. caspia (Eich.) 



D. rostriformis (Desh.) 



D. brardii, Brgn. var. caspia (Grm.) 



GASTROPODA. 



Neritina littorata 

 N. schulzii 

 Hydrobia caspia 

 H. dimidiata 

 H. spica 

 H. stagnalis 

 Eulima conus 



(Eich.) 

 (Grm.) 

 (Eich.) 

 (Eich.) 

 (Eich.) 

 (Linn.) 

 (Eich.)? 



Bithynia eichwaldi (Krynicki.) 

 Lithoglyphus ? caspius (Krynicki.) 

 Planorbis micromphalus (Fuchs. ) ? 



Separating the Mollusca, we have the following list of genera, in which I have 

 added the name of the group of beds in which each genus is first known to occur : 



Corbicula, 



Cardium, 



Adacna, 



Anodonta, 



Dreissena, 



Neritina, 



Hydrobia, 



Eulimus, 



'Bithynia, 



Lithoglypha, 



Planorbis, 



1 sp., Lower Eocene. 



12 sp., Upper Jura. 



4 sp., Lower Pliocene. 



1 sp., Devonian. 



5 sp., Upper Eocene. 



2 sp., Lias. 



4 sp., Middle Jura. 



1 sp., Trias. 



1 sp., Middle Jura. 



1 sp., Lower Pliocene. 



1 sp., Lias. 



It is generally admitted that this Molluscan fauna has its closest affinities with 

 that of the " Congerien " strata of Upper Pliocene age, and I therefore add a list of 

 the latter for comparison. 



* Fossils of " Congerien " Strata. Sandberger, p. 676, etc. 



