OF CONCHOLOGY. 25T 



b. Diam.=lh mill. 

 4. Conulus minutissima, Lea. 



Plate 4, figure 63. 



Globosely turbinate, above obtusely elevated, below con- 

 vex, fuscous, minutely striate ; whorls 4; aperture transverse- 

 ly lunar, umbilicated. 



Diam. 1J, height 1 mill. 



Maine to Pennsylvania, Ohio. 



Distinguished by its small size, striate surface, and well de- 

 veloped umbilical opening. 



Mr. Morse has distinguished this species as the genus Punc- 

 tum, (sub-family Punctinse,) from the peculiar conformation of 

 the buccal plate, which is divided into sixteen distinct pieces. 



This is the smallest of our species. 



GASTRODONTA, Albers. 

 1. Gastrodonta gularis, Say. 



Plate 4, figure 39. 



Sub-conical, shining, yellowish horn-color, translucent ; 

 whorls 7 — 8, striate; suture moderately impressed, aperture 

 transverse, rather narrow, margin sharp, extending beneath to 

 the centre of the base, which is barely perforate or closed ; 

 within thickened at the base by a callus deposit, and having 

 two parallel lamellar teeth, extending nearly to the basal mar- 

 gin of the lip. 



Diam. 7 — 9, height 5 — 7 mill. 



East Tennessee, Georgia, Alabama. 



Sometimes one tooth is wanting;. 



2. Gastrodonta lasmodon, Phillips. 



Plate 4, figure 40. 



Depressed orbicular, shining, corneous, translucent; whorls 

 7, narrow, ver}^ slowly increasing, minutely striate, suture 

 moderately marked ; aperture nearly circular, laminal teeth 

 upon the internal base of the lip ; umbilicus large and deep. 



Diam. 6, height 3 mill. 



East Tennessee, North Alabama. 



Much more depressed than the other species. Is smaller 

 than No. 1, and differs from it in the large umbilicus. 



