A MANUAL OF AMERICAN LAND SHELLS. 37 



Succinea Wilsoni, at Darieti, Ga. Mesodon major extends from tlie Gulf 

 to Abbeville, S. C, coutined to a narrow tract of territory, and also in 

 the Cumberland Subregion. 



The following European species have been introduced by commerce 

 into this region, and still exist at the points named: Stenogyra dccollata, 

 Lin., Turricula terrestris and Pomatia-,aspersa,, Miill., at Charleston, S. 

 C; Coecilianella acicula, Miill., Florida. 



From the list of species peculiar to the Southern Eegion it will be 

 seen that the prevailing form is Polygyra,. a group or genus peculiarly 

 American, represented in the Interior Eegion indeed, but meeting its 

 greatest development here. The presence of Glandina and Veronicella 

 shows, also, the more southern character of land- shell fauna. But the 

 region, and especially that portion of it from whence the fauna was 

 distributed, i. e., the southern extremity of Florida, is still more peculiar 

 in showing the connection between the land shells of the continent of 

 North America and those of the West India Islands and the Spanish 

 Main. Of the species given above (p. 36), Cylindrella jejuna was, per- 

 haps, introduced from Cuba, and BuUmulus Dormani may prove iden- 

 tical with B. maculatus, Lea, of Carthagena. The following species have 

 evidently been introduced* from the West India fauna :t 



Zonites Gimdlachi, Cuba, &c. BuUmulus MarieUnus, Cuba. 



Micro])hysa vortex, Cuba, &c. Strophia incana, Cuba. 



Hemitroohus varians, New Prov- Stenogyra suhula, Cuba, &c. 



idence. gracillima, Cuba, &c. 



CyUndrella Poeyana, Cuba. Ligtms fasciatus, Cuba. 



Macroceramus Kieneri, Cuba. Orthalicns undatus, Cuba. 

 Gossei, Cuba. 



From Yucatan one species has been introduced, Polygyra oppilata. 

 BuUmulus multilineatus was introduced from the continent of South 

 America,! where it has been found at St. Martha, New Granada, and at 

 Maracaibo and Puerto Cabello, in Venezuela. 



Florida has not only received several of its species from the West 

 Indies, but also from its southern extremity it has contributed in return 

 to the fauna of those islands. From hence, no doubt, Zonites arboreus 



* Either by oceanic currents since the formation of the peninsula of Florida, or else 

 from some island of the West India group, now inclosed in the peninsula. It is in- 

 teresting in this connection to refer to the discovery, by Mr. Conrad, of a Tertiary 

 fossil at Tampa Bfly, BidimuJus Floridanus, Conr. 



tAlso several non-pulmonate species, as Helicina suhglobnlosa, Cuba; Ctenopoma 

 rugulosum, Cnha ; Chondropoma dentatum, Cuba. 



t Or from some extinct fanna, which also accounts for its jireseuce at both points. 



