DALL: MOLLUSCA AND BRACHIOPODA. 279 
tinct, not appressed, the anal fasciole forming a sharply limited band immediately 
in front of it; fasciole polished, sculptured with small numerous elevated concave 
wrinkles, with regular wider interspaces ; these wrinkles on the last whorl become 
closer and less prominent; axial sculpture of inconspicuous irregular protractive 
depressions hardly to be distinguished from emphasized lines of growth ; spiral 
sculpture of numerous fine, channelled, incised lines with wider flattened inter- 
spaces, five or six to a millimeter, the whole more or less minutely reticulated by 
the incremental lmes; aperture narrow, the anal sulcus parallel-sided, deep; the 
outer lip arcuate, strongly protractive, thin, sharp, simple; pillar and body with- 
out callus ; pillar straight, twisted, almost pervious at the axis ; canal short, wide, 
slightly recurved. Lon. of shell, 24; of last whorl, 16; of aperture, 12; max. 
diam. 11.5 mm. 
U.S. S. “ Albatross,” station 3365, off Cocos Island, Gulf of Panama, in 1010 
fathoms, ooze, bottom temperature 37° F. U.S. N. Mus. 123,136. Also at 
station 3366, in 1067 fathoms, ooze, temperature 37° F. (type). 
This differs from the typical P. agonia in having more numerous, finer and less 
prominent spirals which are not cut into short segments by the incremental lines, 
and a higher and more acute spire of at least one more whorl, giving the whole 
shell a more elevated and slender aspect. 
Pleurotomella (Gymnobela) egregia Da tt, n. sp. 
Shell of the same type as the preceding species, but larger and proportionally 
much stouter, of the same pinkish brown color and delicate construction, and 
about five whorls; spire subconoid, with distinct suture and well-rounded whorls ; 
sculpture similar to that of P. agonia but more emphatic, particularly the arcuate 
wrinkles which cross the anal fasciole; aperture wide, anal sulcus deep and 
rounded, the outer lip thin, roundly produced in front, no perceptible callus on 
the body; pillar thin, twisted, obliquely truncate in front; canal very short and 
rather contracted, axis not pervious. Lon. of shell, 23; of last whorl, 18; of 
aperture, 18; max. diam. 11.7 mm. 
U. S.S. “ Albatross,” station 4656, 100 miles west of the Peruvian coast, in 
2222 fathoms, mud, bottom temperature 35°.2 F. U.S. N. Mus. 110,610. 
In this species the spiral sculpture is well defined and emphatic over the whole 
surface. : 
Pleurotomella (Gymnobela) isogonia DaLt, n. sp. 
Plate 4, figure 3. 
Shell short, stout, biconic, white or subtranslucent with a yellowish periostracum ; 
apical whorls much eroded, indicating for the whole shell six or more turns; suture 
appressed, whorl in front of it steeply descending to a very strong keel at the 
