NO. 2 PYRAMIDELLID MOLLUSKS — BARTSCH 35 



that vary from mere lines to broad pits. They are best visuaHzed for 

 strength and spacing by viewing our detailed sketch (pi. 5, fig. 3b). 

 The suture is well impressed and rendered wavy by the strong ribs 

 at the summit of the whorls. The last whorl is somewhat inflated at 

 the periphery which is well rounded. On the last whorl the axial 

 ribs become enfeebled. They pass over the hemispherical base as 

 weak extensions to the umbilical chink. No spiral sculpture is present 

 upon the base. All these sculptural features of the last whorl and base 

 speak for old age and senescence. The aperture is ovate; the colu- 

 mella is slender, thin, and anteriorly revolute; the parietal wall is 

 glazed by a thin callus; the outer lip is reinforced within by two 

 spiral cords, of which the basal is broad and low. 



The type, U.S.N.M. No. 561693, comes from the Pliocene of North 

 St. Petersburg, Fla. It has 9 whorls remaining and measures : Length 

 6.2 mm., diameter 1.9 mm. U.S.N.M. No. 561694 contains another 

 specimen, and two more are in the collection of the A.N.S.P. 



The more slender and different spiral sculpture readily distinguishes 

 this specimen from Mormiila pilsbryi (p. 34). 



I take pleasure in naming this species for Mrs. Imogene Strickler 

 Robertson, who served the American Malacological Union as faithful 

 secretary-treasurer for many years. 



MORMULA TESKEYAE, new species 

 Plate 6, figures la, b 



Shell elongate-turrited, cream-yelloAv. All the early whorls are 

 lost, the last 5 only remaining. These are well rounded and marked 

 by strong retractively slanting axial ribs which are of the same 

 strength from the suminit to the periphery, where they terminate. 

 Of these ribs 16 are present upon all the whorls except for the first, 

 which has 14. The intercostal spaces are about as wide as the ribs 

 and are crossed by 18 incised grooves that vary in strength from 

 mere lines to broad pits. Their variation in width and spacing are 

 best visualized by examining the detailed sketch (pi. 6, fig. ib). The 

 suture is well impressed and rendered wavy by the strong ribs at 

 the summit of the whorl. The periphery is well rounded. The base 

 is hemispherical, smooth, and without sculpture. The aperture is 

 ovate; the columella is slender and provided with a strong fold a 

 little below its insertion. The parietal wall is glazed by a thin callus ; 

 the outer lip is reinforced within by four spiral cords. 



The type, U.S.N.M. No. 561695, comes from the Pliocene of North 

 St. Petersburg, Fla. It consists of the last 5 whorls and measures : 

 Length 4.1 mm., diameter 1.2 mm. 



