56 BULLETIN 90, UNITED STATES NATIONAL MUSEUM. 



shell is yellowish or pinkish white with obscure, line, opaque, axially 

 directed streaks, and varies a good deal in size. 



MARGINELLA IMPAGINA, new species. 



Plate 12, fig. 4. 



Shell minute, smooth, with indication of what may possibly be 

 two spiral color bands on the last whorl, with a gently tapered spire 

 of about 4 whorls, the suture obscured by a. coat of enamel which 

 covers the entire spire; shell fusiform; aperture sublunate; outer lip 

 ascending a little from the suture behind, arcuately projecting in the 

 middle, thin, simple with (in the specimen) no varix; canal wide, 

 shallow; pillar with four equal and equally spaced oblique plaits, 

 the anterior plait situated on the edge of the pillar ; body with little 

 or no callus. Length 5, maximum diameter 2.7 mm. 



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



Type-specimen from the Post collection, U. S.Nat.Mus. No. 165060. 



This specimen may be slightly immature. 



MARGINELLA POSTI, new species. 

 Plate 12, fig. 6. 



Shell small, smooth, of about 4 whorls, which are more or less ob- 

 scured by a coating of enamel covering the entire spire, solid, slender ; 

 on the last whorl are a few faint axial sulci or incremental markings ; 

 terminating the whorl in the adult is a heavy wide varix, the pos- 

 terior edge of which is sharply elevated above the general surface; 

 aperture narrow behind, wide in front; outer lip varicose, simple, 

 thicker in the middle, receding to the canal, without internal lirae; 

 body smooth not callous; pillar shorter than the aperture with four 

 subequal, equidistant plaits, the anterior set on the twisted edge of 

 the pillar; canal short, wide, with a continuation of the varix mar- 

 ginating it on the back. Length 6.4, maximum diameter, 3.5 mm. 



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



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

 165057. 



MARGINELLA INTENSA. new species. 



Plate 10, fig. 8. 



Shell small, short, solid, smooth, with a short spire, obscured by a 

 coat of enamel covering it entirely, and about 3 whorls ; aperture nar- 

 row; outer lip produced behind over nearly half the penultimate 

 whorl, heavily smoothly varicose, the varix distinctly limited behind, 

 marginating the lip and canal, internally smooth, thicker in the 

 middle; body with a slight wash of enamel; pillar with four low, 



