328 PROCEEDINGS OF UNITED STATES NATIONAL MUSEUM 
at right angles transversely to the axis of the shell, the posterior plate 
strongest, the others diminishing anteriorly, the last one separated by 
quite a space from the anterior edge of the column; notch deep, not re- 
flected. Lon. of shell,.6.00; of last whorl, 4.50; of aperture, 3.2; max. 
lat. of shell, 2.5; of aperture, 1.00™™. 
Habitat.—On the reefs at Key West, at low water; rare. This pretty 
little shell resembles a Mitra, but also recalls the forms named Mitro- 
morpha, by Carpenter, which seem to stand conchologically between 
the cones and mitras. 
Mangilia stellata Stearns.* 
Key West, abundant on the reefs at low water. I have not been able 
to compare this with a typical specimen, but there is little doubt of its 
identity. 
Mangilia cerina Kurtz and Stimpson. 
Sarasota Bay, mud flats between tides, plenty; also in similar sitna- 
tions at Cedar Keys. 
Drillia ostrearum Stearns. 
Key West, on reefs at low water, rare. 
Drillia albomacvlata D’Orb.* 
Sarasota Bay, on mud flats between tides, rare. This does not agree 
precisely with D’Orbigny’s figure, but the differences do not seem to be 
of specific value, and may be due to defects in the figure. I have not 
been able to compare types. 
Drillia thean.s. (Plate X, Fig. 5.) 
Shell elongated, slender, eight whorled, colored olivaceous like the 
leaves of tea which have been steeped, weathering ashy; apex small, 
rather blunt; whorls moderately convex, covered with a shining very 
thin epidermis, marked by silky lines of growth, sculptured by about 
eleven somewhat oblique slightly curved ribs, which are broadest, stout- 
est, and paler than the rest of the shell on the periphery, fading away 
toward the sutures and not distinctly differentiated from the inter- 
spaces, somewhat irregularly waved, and concave anteriorly; also by 
evanescent spiral striz not always visible and eight or ten raised spiral 
threads on the anterior third of the last whorl; notch deep, rounded, 
leaving no fasciole; canal short, straight; sutures distinct, sligutly 
appressed; aperture wide, short, internally claret brown; inner lip with 
a slight callus; outer lip much curved forward, polished and smooth 
within. Lon. of shell, 15.0; of last whorl, 8.0; of aperture, 5.5; max.” 
lat. of shell, 5.2™™. 
Habitat.—Sarasota Bay, rare, on mud flats between tides. Two 
specimens. 
Drillia leucocyman.s. (Plate X, Fig. 8.) 
Shell small, dark, solid, strongly sculptured, with about seven whorls, 
of which the basal color is a very dark olivaceous brown; the interior 
