36 TERRESTRIAL AIR-BREATHING MOLLUSKS. 



ptistula, pustuloides, and Pupa modica. Tr'iodopsis Hopetonensis ex- 

 tends only along the Atlantic alluvial Region. Bidinmlus dealhatus 

 is also distributed over the whole Region, from North Carolina to 

 Texas, and has spread northward to Arkansas and Kentucky. Suc- 

 cinea campestris extends along the Atlantic coast as far as South Caro- 

 lina, as does also Zonites cerinoideiis, even into North Carolina and 

 Virginia. Foli/gyra espiloca and PosteUiana have been noticed thus far 

 in the southeastern corner of Georgia. The former also at New Orleans 

 and Indianola. Sitccinea Wilsoni, at Darien, Ga. Mesodon major ex- 

 tends from the Gulf to Abbeville, S. C, confined to a narrow track of 







territory. 



The following European species have been introduced by commerce 

 into this Region, and still exist at the points named : Stenogyra decol- 

 lata, Lin., Tury^cida terrestris and Pomatia aspersa, Miill., at Charleston, 

 S. C. ; Coecilianella acicida, Miill., Florida. 



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

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

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

 greatest development here. The presence of Glandina and Ve^'onicella 

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

 Region, and especially that portion of it from whence the fauna w^as 

 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. 35), Cylindrella jejuna was, per- 

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

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

 evidently been introduced ^ from the West India fiiuna : ^ — 



Zonites Gundlachi, Cuba, etc. Bulimulus Marielinus, Cuba. 



Patula vortex, (uha, etc. Strophia incana, Cuba. 



Hemitrochus varians, New Providence. Stenogyra subula, Cuba, etc. 

 Cylindrella Poeyana, Cuba. gracillima, Cuba, etc. 



Macroceramus Kieneri, Cuba. Liguus fasciatus, Cuba. 



Gossei, Cuba. Orthalicus undatus, Cuba. 



From Yucatan one species has been introduced, Polygyra ojypilata. 



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

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

 ing in this connection to refer to the discovery, by Mr. Conrad, of a Tertiary fossil at 

 Tampa Bay, Bxdimus Floridanus, Conr. See also below, p. 40. 



2 Also several non-pulmonate species, as Helicina suhglohulosa, Cuba ; Ctenopoma 

 rugulosum, Cuba; Chondropoma dentatum, Cuba. 



