VOLVULA. 237 



more ovate than that of Orbigny, and I find specimens agreeing with 

 both figures in form, with others which appear more or less inter- 

 mediate. This species differs from V. acuminata Brug, in being one 

 quarter shorter with the same width, in having a well marked um- 

 bilical chink, and an apical process averaging shorter in specimens 

 of the same size. (Dall). 



The F. minuta of Miss Bush, which Dall believes identical with 

 acuta, is described as follows : 



V. minuta (pi. 26, fig. 57), 



Shell very small, spindle-shaped, thin, semi-transparent, white, 

 destitute of sculpture with the exception of three or four very indis- 

 tinct, punctate, spiral lines on the base. Aperture very narrow, 

 gradually expanding anteriorly from about the middle, with a reg- 

 ularly curved outer lip. Columella with a slight twist or fold, with 

 a very small umbilical chink behind it. Epidermis indistinct. 

 Length of the largest specimen, 2*5, breadth, 1 mill. 



V. BUSHII Dall. Unfigured. 



This species is stouter, and its posterior process more acutely 

 pointed than in V. acuta ; its posterior end is more inflated and 

 blunt than in V. acuta or acuminata, and the little sharp spine rises 

 more abruptly from this dome. The anterior part of the shell is 

 somewhat narrower than the posterior part, with very straight sides 

 and columella, toward which it is evenly rounded in front. There 

 is along chink behind the pillar, a faint wash of callus on the body, 

 and fine microscopic spiral striae over the polished surface. The 

 color is greenish-white of a cretaceous quality. The columella is 

 slightly reflected, but not twisted. Lon. 4'6 ; lat. 2'3 mill. (Dall}. 



Station 2602, 36 miles S. % W.Jrom Cape Hatteras, N. C., in 124 

 fms., sand, (U. S. Fish Commission). 



V. bushii DALL, Blake Gastr., p. 51. 



V. ASPINOSA Dall. Unfigured. 



Shell white or yellowish, opaque, the young translucent, rather 

 stout, ovate, the aperture as long as the shell, very narrow behind, 

 wider in front, the outer lip sharp-edged, thickened inside, evenly 

 rounded to both extremities, its middle part nearly straight, the left 

 or opposite side of the shell much more arched than the right side; 

 surface with well-marked incremental lines, numerous small micro- 

 scopic striae a little stronger toward the extremities ; columella thick, 





