24 



LAND AND FRESH-WATER SHELLS OF N. A, 



VOL. IIL 



Fig. 43. 



Fig. 44. 



Vivipara con- 

 tectoides,yo\xng. 



Fig. 45. 



Paludinu linearis, KiisTEK, in Cli. ed. 2, 10, pi. ii, f. G-9 ; p. 19, pi. iv, f. 



4 (1852). 

 Helix vivipara, Eaton, Zool. Text-Book, 196 (1826). 



Has been found in Floi'ida, Georgia, South Carolina, Alabama, 

 Arkansas, Missouri, Illinois, Indiana, Michigan. 



The specimen (Fig. 41) from which the above description is 

 drawn is probably a male. It is the most scalarj- 

 form of all that I have seen. The species is varia- 

 ble, the degrees of globoseness being 

 numerous. 



The umbilicus is rarely entirely closed, 

 even in young shells. 



The number and disposition of bands 

 is constant in all the specimens before 

 me ; the lower band sometimes is ex- 

 panded so as to surround and enter the umbilicus. 



The species is readily distinguished from V. georgmna by 

 its perfect apex, by the greater globoseness of its whirls — they 

 being more loosely convoluted, and by its 

 more shining surface. Its 

 epidermis is more delicate, 

 and does not peel off like 

 that of georgmna. 



Vivipara contectoides re- 

 ceives its name from its 

 strong resemblance to the 

 V. contecta of Europe. It 

 has been by some authors 

 considered identical with 

 that species, and with the 

 exception that the American form has four spiral bands upon the 

 body whirl while the European is described as having but three, 

 I can detect no specific differences between them. It is more 

 upon its geographical distribution that I base my opinion of its 

 being distinct. Our species is found over an area very much 

 vaster than that inhal)ited by its European analogue. It is not 

 one of the fiuviatile species of the circumpolar or boreal regions, 

 common to the three continents, as it is not found farther north 

 than the great lakes. I am inclined to believe that, as with the 

 exception of these circumpolar species the land and fresh-water 



Fig. 46. 



Vivipara contecta, MiU. 



Vivi2)ara 

 vivipara, Lin. 



