222 



REPORT — 1856. 



The freshwater and land shells described in this work, pp. 273-308, appear 

 to belong exclusively, either to the general North temperate fauna of the old 

 world, or to the local fauna of the district. They are distributed by Mid- 

 dendorff under three heads, pp. 389 e< seg-. (1) Circumpolar Fauna : Unio 

 margaritifera, Pianorbis albus, Lininaeus stagnalis and palustris, Physa hyp- 

 norum, Succinea putris, Helix pulchella, pura and fulva, Achatina lubrica, 

 Vitrina pellucida. (2) Boreal Fauna: Unio pictorum and batavus, Anodonta 

 cellensis and anatina, Pisidium obliquura, Cyclas cornea and calyculata, 

 Pianorbis corneus, compianatus, contortus, leucostoma and vortex, Limnaeus 

 auricularius, truncatulus, leucostomus, Physa fontinalis, Paludina Kilcxii and 

 tentaculata, Valvata piscinalis, Helix ruderata, Schronkii, carthusiana and 

 hispida, and Bulimus obscurus. (3) Central Asiatic Fauna : Unio Dahuricus 

 and Mongolicus, Anodonta herculea, and Limnsus Gebleri. 



The author enters at considerable length, pp. 351-389, into the influence 

 of Zones, Depths, Temperature and Saltness on the distribution and changes 

 of moUusks; and gives full details of the peculiarities of several specific and 

 generic forms, pp. 330-342. In pp. 309-4'63, the author distributes the 

 Russian shells into their various Zoological provinces. With the Aral-Kas- 

 pian, the Black Sea* and the very limited Baltic faunas, we have now no 

 concern. The Polar fauna (p. 318 et seq.) is divided into three sections : — 

 A. The Atlantic species, 30 in number. B. Those of the Behring Sea, 26 ; 

 and C. the Circumpolar species. Si. To this list are added 50 species, which 

 have not yet been found in the Russian dominions. 



* MiddendorfF gives the following species as common to the temperate latitudes on both sides 

 of the Atlantic : — Littorina rudis, Fusus muricatus, Crcpidula unguiformis, Dentalium denialis, 

 Anoviia ephippium, Solen ensis, Pecicn varius, Lima squamosa. Also the following as common 

 to the Mediterranean and the West Indies; — Conus Mcditerraneus, Columbella mercatoiia, 

 Nassa crenulata, Liltoriim muricata and neritoides, Cerithium lima, Tellina carnaria, and 

 Rotella lineata. Pp. 346-7. 



