MUSEUM OF COMPARATIVE ZOOLOGY. 



215 



From the various sources indicated above the southern extremity of 

 Florida has become inhabited by about seventy species of land shells, a 

 number small in comparison with those found in the Cumberland Sub- 

 Region (see p. 211), but large when compared with those found in the 

 great Interior Region. 



In addition to those species apparently originating in the peninsul; 

 of Florida and thence spreading over the whole Southern Region, there 

 is found within its limits a number of species confined to its southwest- 

 ern portion. These seem restricted to the southern part of Texas, which 

 may be considered an offshoot of the Mexican fauna as shown by the 

 presence of the genera characteristic of that country, such as Holospira, 

 Bulimulus, and Glandina. "Within the region, however, are many 

 species peculiar to it, but belonging to the subgenera characteristic of 

 North America, such as Polygyra and Mesodon. It seems, therefore, 

 best to consider Texas as belonging equally to the fauna of North America 

 and of Mexico, being the point where the two overlap. As the limits 

 of the region are ill defined, several species extralimital to the State of 

 Texas are included in the following catalogue of the Texan Region: — 



Glandina Vanuxemensis. 

 decussata. 

 parallela. 

 bullata. 

 Texasiana. 

 Zonites significans. 



caducus. 

 Fatula incrustata. 

 Helix Hubbardi. 

 ventrosula. 

 Hindsi. 

 Texasiana. 

 triodontoides. 

 Mooreana. 

 tholus. 

 hippocrepis. 

 Jacksoni. 

 Ariadne. 



Helix vultuosa. 

 divesta. 

 Roemeri. 

 Berlandieriana. 

 griseola. 

 Bulimulus patriarcha. 

 alternatus. 

 Schiedeanus. 

 Macroceramus Gossei. 

 Holospira Goldfussi. 

 Roemeri. 

 Stenogyra octonoides. 

 Pupa pellucida. 

 Succinea Haleana. 



concordialis. 



luteola. 



Salleana. 



Of the above Helix Jacksoni and Zonites significans are included 

 with great hesitation. They are found at Fort Gibson, in Indian Ter- 



