FAUNA OF ORTHAULAX PUGNAX iiONE. 27 



subsequent whorls strongly marked by distinct, equal, equally spaced, 

 elevated, retractive axial threads ; base rounded, with a narrow chink 

 in the umbilical region, under the reflection of the pillar lip ; aper- 

 ture as figured, with a reflected peritreme, the reflection of the poste- 

 rior half of the outer lip narrow, the anterior part with a prominent 

 nodule at the middle of the lip, in front which the lip is thickened 

 and more strongly reflected; pillar arcuate, thickened; body with a 

 layer of enamel, a faint subsutural thickening, and a narrow sinus 

 at the junction of the outer lip ; the latter rises slightly at the suture 

 near the aperture. Height of shell 10.7, maximum diameter 4.5 mm. 



Tampa silex beds. Ballast Point, Tampa Bay, Florida. 



Type specimen from the Post collection, U. S. Nat. Mus. No. 

 165013. 



BULIMULUS (HYPERAULAX) STEARNSII Ball. 



Plate 2, fig. 4. 



BuUmulus (? Anctus) stearnsii Dall, Trans. Wagner Inst., vol. 3, pt. 1, 

 p. 7, pi. 1, fig. 12, Aug. 1890. 



Tampa silex beds, at Ballast Point, Tampa Bay, Florida. One 

 specimen, collected by Dall. U. S. Nat. Mus. No. 111964. 



This is smoother than any of the other species, more slender and 

 elongated. 



BULIMULUS (HYPERAULAX) TORTILLA, new species. 

 Plate 1, fig. 2. 



Shell small, subfusiform, blunt, with about five whorls, the nucleus 

 in the type-specimen somewhat defective; suture distinct, slightly 

 appressed; whorls slightly rounded, the apical two or three smooth, 

 the later whorls sculptured with numerous close-set axial retractive 

 threads, equal, equally spaced, and with equal furrows between them; 

 base slightly attenuated, imperforate, with a chink behind the reflec- 

 tion of the pillar lip; aperture subovate; peritreme completed by a 

 rather thick smooth parietal callus, with a feeble sinus or shallow 

 channel at the sul^sutural angle; outer lip thin behind, thickened in 

 the middle ; anterior portion, together with the rest of the peritreme, 

 thickened, simple, and slightly reflected ; margin smooth. Height 8, 

 maximum diameter 3.8 mm. 



Tampa silex beds. Ballast Point, Tampa Bay, Florida. 



Type-specimen from the Post collection, U. S. Nat. Mus. No. 

 165015. 



BULIMULUo (HYPERAULAX) REMOLINA, new species. 



Plate 1, fig. IS. 



Shell small, slender, thin, moderately acute, with five whorls sep- 

 arated by a distinct, slightly appressed suture; nucleus small, 

 smooth, rapidly enlarging; subsequent whorls moderately convex, 



