90 PROCEEDINGS: BOSTON SOCIETY NATURAL HISTORY. 
No. of U.S.F.C. 
Depth Temp. 
Disposition of 
Cat. no. spec. sta. 
Locality. (fms.). 
material. 
203,772 1 
Wood's Holl, Mass. 
U. S. nat. mus. 
45,455 1 865-867 
Martha's Vineyard, Mass. 65 68° 
U U II 
94,826 1 
II 11 u 
" " " 
Turbonilla (Pyrgiscus) winkleyi new species. 
PI. 12, figs. 35, 37. 
Shell elongate-conic, wax yellow. Nuclear whorls small, two and 
one quarter, depressed helicoid with their axis almost at right angles 
to that of the succeeding turns; about one quarter immersed in the 
first post-nuclear whorl. Post-nuclear whorls ornamented by moder- 
ately strong axial ribs of which there are 22 upon the 1st, 2d, and 3d; 
20 upon the 4th, 5th, 6th, and 7th; 24 upon the 8th; 28 upon the 9th; 
and 22 upon the penultimate turn. Intercostal spaces of varying 
width, crossed by spiral striations of var_ying width, of which four 
equal and equally spaced occur upon the 1st; 6 unecjual ones upon 
the 2d; 7 upon the 3d, 4th, and 5th; 8 upon the 6th; 10 upon the 7th; 
11 upon the 8th; 13 upon the 9th and penultimate whorl. Base 
rather short, well rounded, marked by the feeble continuations of the 
axial ribs which disappear entirely shortly after crossing the rounded 
periphery and about 15 feeble, wavy, irregularly spaced spiral stria- 
tions. Aperture suboval; outer lip thin, showing the external sculp- 
ture within; columella slender, curved, and slightly revolute. 
The tyjDe, cat. no. 203,776 U. S. N. M., comes from Wood's Holl, 
Mass. It has eleven post-nuclear turns and measures: length, 7.9 
mm.; diameter, 2.0 mm. 
This is probably the most abundant and variable species on the 
Atlantic coast. The above description shows that the scidpture in 
a single specimen, the tj'pe, is quite variable. The variability is 
emphasized when we examine such a wealth of material as has been 
at our disposal. The axial ribs may be crowded or distinctly spaced, 
the spiral markings may vary not only in numbers but also in strength, 
from deep lines of pits, to fine striations. It is one of those forms in 
which scarcely two indi\iduals present exactly the same phase of 
ornamentation, resembling in this respect Turbonilla (Pyrgiscus) 
tenuicula Gould, of the west coast of America. The yellow color 
which appears on the surface like an epidermis, and the shape, serve 
as a guide to this form. 
