X FRANCE AND GERMANY 289 



species occur which are confined to the high grounds of south 

 central Europe. Among these are Helix holoserica Stud., H, 

 personata Lam., H. hidens Chem., H. depilata Drap., H. cobresicma 

 Alt., H. alpina Faure. 



The Pleistocene deposits of the valley of the Somme tell the 

 same tale as those of eastern England, containing as they do 

 species and even genera whose northern range is now much more 

 limited. The Eocene fossils from the Paris beds show most re- 

 markable relationships to genera now existing in the West Indies 

 and Central America. Others again indicate affinities with India. 

 Thus we find Ceres^ Megalomastoma^ and Tudora by the side of 

 Leptopoma^ Faunus^ and Paludomus. 



G-erincmy. — The Mollusca of the plains of northern Germany 

 are few and not striking, and exhibit little difference from those 

 of our own islands. In the mountainous districts of the south 

 and south-east, a number of new 

 forms occur, amongst which are 3 

 species of Daudebardia, a remarkable 

 carnivorous form, with the general 

 appearance of a Vitrina; 24 of Clau- 

 suia.m^u} j-upa,^e\Q\^imiLiminus, ^^^ . ^j^^ ^^^^^^. ^^ ^^ pulmonary 



3 of the Campiflaea group of Helix, orifice. (After Pfeiffer.) B, shell 



stragglers from the Italo-Dalmatian °^ ^- '"■^" ^^'^ ^- Germany, 

 fauna, and 1 of ZoJiites proper. Our familiar Helix aspersa is 

 entirely absent from Germany. There are only 4 land oper- 

 culates — Pomatias 2, Acicula 1, Cyclostoyna 1, all of which occur 

 exclusively in the south. BitJiynella and Vitrella, two minute 

 forms of fresh-water operculates akin to Hydrohia, occur through- 

 out the district. 



Northern Russia and Siberia. — This vast tract extends from 

 eastern Germany to the Amoor district. It is exceedingly poor 

 in Mollusca, and is chiefly characterised by the gradual disap- 

 pearance, as we proceed eastward, of European species. There 

 are a few characteristic Siberian Mollusca, closely allied to 

 European forms, and in the extreme east a new element is 

 introduced in the appearance of types which indicate Chinese 

 affinities. The v/hole district may be regarded as bounded to the 

 south by a line drawn from Lemberg to Moscow, and thence to 

 Perm ; passing south of the Ural mountains, it includes the 

 whole basins of the rivers Obi, Yenesei, and Lena, coinciding with 



VOL. Ill U 



