216 BULLETIN OF THE 



ritory.* They are more related to the fauna of the Cumberland Sub- 

 Region than that of Texas. 



Besides the species characteristic of the North American fauna which 

 Texas has as a portion of the Southern Region of the great Eastern 

 Province, we find in the' above list two species peculiar to it of the 

 characteristic American subgenus Mesodon, Helix lioemeri and JL, 

 divesta.'f 



Several species on the list have been introduced from other regions,! 

 such as Helix Hubbardi,% a Jamaica species, as well as Macroceramus 

 Gossei, a Cuban species, which is also found on the Florida Keys. Patula 

 incrustata from Cuba, as well as Pupa pellucida and Stenogyra octo- 

 noides. 



Of the remaining species on the list, sixteen have actually been found 

 in Mexico ; probably all will be, as there seems no well-defined boundary 

 here between the North American and Mexican fauna. 



Bulimidus serperastrus, Say, although actually found in Texas, is evi- 

 dently a member of the Mexican fauna, and is therefore omitted from 

 my list. 



The characteristic of Texas appears to be the great preponderance of 

 the subgenus Polygyra, of the type of H. Texasiana, while the type of 

 Florida, the septemvolva, is quite wanting. The great abundance of indi- 

 viduals is also remarkable, showing the Region to be peculiarly adapted 

 to pulmonate life. In the number of its species, also, the Texas Region 

 is favored ; by adding to the above list of peculiar species those which 

 it has in common with all of the Eastern Province, and also those of the 

 Southern Region, we find a total of seventy species, the same number as 

 found in Florida. 



* A. Binncy, Terr. Moll , 1. 122, gives the limits of the corresponding " Southern 

 Interior Section " such as would include these species. Several of the species of East 

 Tennessee, also, have been found in Arkansas, — a fact also favoring a wider limit 

 to the Cumberland Sub-Region. 



t This species has not actually been found within the limits of the State of Texas, 

 but in the neighboring State of Arkansas and in Mississippi. To it may be applied 

 the remarks on Zonitrs mynificans and Helix Juchsoni on p. 21.";. 



\ Either by commerce, by oceanic current-, or from some former molluscous fauna 

 of which these now isolated localities were offshoots. 



ij Since the above was written, this species has been found by Dr. Newcomb near 

 Savannah, Ga. It may therefore prove a widely distributed American species. In 

 Jamaica it is known as If. Yendramtana, Glovne. 



