Binney on Terrestrial MoJlushs. 159 



wliole Atlantic coast. It has also been found in Texas, 

 (Riiemer.) 



Gould mentions its being said to have been found living 

 with a Planorhis at Windsor, Vt. If so, it must be adapt- 

 ed to a remarkable ditterence of station, being usually 

 found near the sea. Pfeiffer also gives Vermont as the 

 habitat, probably on the above authority. 



Remarks. This shell is familiar to all those who have 

 collected among the salt marshes of Massachusetts Bay. 

 Around Boston it is found not far below high-water-mark, 

 often crawling up the stems of grasses, as if to avoid the 

 returning tide. 



The shell when young is quite pretty, being shining and 

 often variegated by the revolving bands. But few mature 

 shells are met with in a perfect condition. They are 

 usually much eroded. From the toothless outer lip to 

 that bearing a heavy callus ridged with transverse laminse, 

 every intermediate variety is found. The absence of the 

 laminaB is equally common in mature and young shells. 



Authentic specimens of this species are still preserved 

 in the collection of the Academy of Natural Sciences of 

 Philadelphia. 



The original descriptions of Mittre and Deshayes are 

 given below. I have seen authentic specimens of neither 

 of their shells. The descriptions are merely copied by 

 Pfeiffer, in the works referred to in the synonymy. 



Say designates by the name of lineatus, a form peculiar 

 for its revolving lines or bands and more narrow base of 

 the aperture, (vid. Binn. ed. p. 85.) I have met with none 

 sufficiently marked to form a variety, much less a distinct 

 species. The revolving lines are very commonly found on 

 young specimens. DeKay mentions this as var. a, Pfeiffer 

 as p'. The latter author thus describes a var. 7. 



Anfractu ultimo infra suturam subexcavato, minute spiral! tcr 



