ANCYLUS TARDUS, Say. 



PLATE 1. FIG. 3. 

 A. testa parva, regular!, elliptica; elevata, apice obtuso. 



SYNONYMS AND REFERENCES. 



w5. TARDUS, SAY. Disseminator, Jan. 15th, 1830. Mrs. 



Say's reprint, p. 26. 

 ADAMS. Thompson's History of Vermont. 



DESCRIPTION. 



SHELL pale and delicate, elliptical; apex ob- 

 tuse, elevated; posterior and lateral slopes sub- 

 rectilinear, anterior slope convex. 



DIMENSIONS. Long. 0.25, lat. 0.16, elev. 0.13 

 inch. Adams. 



GEOGRAPHICAL DISTRIBUTION. Found in the 

 Wabash, and in Vermont. 



OBSERVATIONS. 



Higher, shorter, and more darkly coloured 

 than A. depressus, and has the apex more 

 nearly central. It is proportionally broader 

 than A. rivularis, and not perceptibly widened 

 before. 



