80 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. 12$ 



upon the second, 14 upon the third, and 15 upon the last whorl. The 

 periphery is marked by a strong, deep sulcus, which is bordered 

 basally by a strong nodulose spiral cord. The rest of the base is well 

 rounded and marked by slender threadlike continuations of the axial 

 ribs. Aperture ovate; columella curved and provided with a fold at 

 the umbilical chink ; parietal wall covered by a moderately thick callus ; 

 outer lip thin and strongly curved. 



The type, U.S.N.M. No. 561670, comes from the Pliocene of North 

 St. Petersburg, Fla. It has almost 4 postnuclear whorls and measures : 

 Length 1.2 mm., diameter 0.7 mm. 



It is named for Mrs. Edna G. Gordon, one of the St. Petersburg's 

 enthusiastic shell students. 



FARGOA, new genus 



Shell minute, pupoid, having axial ribs and four strong spiral cords 

 that render the ribs nodulose on the first three whorls and less so 

 on the fourth. The axial ribs and the first two spiral cords are more 

 closely approximated than the rest and form a dumbbell-shaped sculp- 

 ture below the summit of the whorls. The base is marked by spiral 

 cords. 



Type: Fargoa calesi, new species. 



KEY TO THE SPECIES OF FARGOA 



Shell slender archeri 



Shell stout calesi 



FARGOA CALESI, new species 

 Plate 16, figure 2 



Shell minute, pupoid, cream-yellow. Nuclear whorls almost com- 

 pletely obliquely immersed in the first postnuclear turn. The post- 

 nuclear whorls are moderately well rounded and crossed by strong 

 retractively slanting axial ribs, of which 18 are present upon the 

 second, 20 upon the third and the last whorl. The spiral sculpture 

 consists of four cords, which equal the axial ribs in strength and 

 which form strong nodules at their junction. The first spiral cord 

 is at the summit and is a little nearer the second cord than that is to 

 the third. The first two cords in conjunction with the axial ribs pro- 

 duce a dumbbell-like effect while the spaces between the second and 

 third spiral cord are much more deeply incised. The nodules on the 

 first three cords are about equal; those on the fourth cord are much 

 weaker and almost let this cord appear smooth. The suture appears 



