148 AMERICAN SPECIES OP VERTIGO. 



STUPAKOFF, Nautilus vii, 135 (Allegheny Co., Pa.). PRIME, 

 Nautilus viii, 70 (Long Island, N. Y.). GARDNER, Naut. viii, 

 76 (Long Island). SARGENT, Naut. ix, 89 (Clearwater, 

 Minn.). PLEAS, Naut. vii, 68 (Henry Co., Ind.). Pupa 

 millium SOWERBY, Conch. Icon, xx, pi. 18, f. 164. 



Gould's description and figure are not quite correct in some 

 points ; evidently the columellar lamella and lower palatal fold 

 were not fully seen. The color of the shell is cinnamon or 

 paler. The last whorl has an external impression over the 

 lower palatal fold; there is a swelling in front of the im- 

 pression and below a deeper impression which runs to the lip, 

 over the upper palatal fold. The angular lamella is high, 

 short, and situated inward from the insertion of the outer 

 lip. The parietal is high and long, entering deeply. The 

 high columellar lamella enters horizontally at first, then 

 turns downward, being crescent-shaped. (Its downward con- 

 tinuation was mistaken by Gould for * ' a tubercle at its base " ) . 

 The upper palatal fold is long and high, slightly curved. 

 Lower palatal is a little immersed, high, thin and enters to 

 the dorsal side, where it curves downward (fig. 5). Both 

 palatal folds are rather thick and tapering at their outer ends. 

 The basal fold is somewhat immersed, short and high. There 

 is sometimes a small, tubercular suprapalatal fold. The outer 

 lip is somewhat expanded and strongly biarcuate. The 

 parietal callus is generally rather thick. 



Length 1.75, diam. 1 mm. ; 5 whorls. Cleveland, Ohio, fig. 1. 



Length 1.38, diam. 0.8 mm. ; 5 whorls. Cleveland, 0., fig. 3. 



Length 1.65, diam. 0.85 mm. Vermont, fig. 7. 



Length 1.4, diam. 0.9 mm.; 4% whorls. Volusia Co., Fla., 

 fig. 6. 



V. mUium shows but little variation in the teeth, though in 

 some examples the lower palatal fold emerges further than in 

 others, and the degree of curvature of its inner end varies 

 somewhat. The size and contour of the shell, however, are 

 quite variable, as will be seen by reference to the measure- 

 ments and figures. In one lot I found the length from 1.38 

 to 1.75 mm. 



The shortest specimens seen (but generally associated with 



