BALL : MOLLUSCA AND BRACHIOPODA. 279 



tinct, not appressed, the anal fascicle forming a sharply limited band immediately 

 in front of it; faseiole polished, sculptured with small numerous elevated concave 

 wrinkles, with regular wider interspaces ; these wrinkles on the last M^borl become 

 closer and less prominent ; axial sculpture of inconspicuous irregular protractile 

 depressions hardly to be distinguished from emphasized lines of growtli ; 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 lines ; 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. 

 diara. 11.5 mm. 



U. S. S. "Albatross," station 3365, off Cocos Island, Gulf of Panama, in 1010 

 fathoms, ooze, bottom temperature 37° T. 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 Dall, 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 wiiorls ; 

 sculpture similar to that of P. agonia but more emphatic, particularly the arcuate 

 wrinkles which cross the anal faseiole ; aperture wide, anal sulcus deep and 

 rounded, the outer lip thin, roundly produced in front, no perceptible callus ou 

 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, 13; 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. 



PleurotoEciella (Gymnobela) isogonia Dall, n. sp. 



Pinto 4, nRurc 3. 



Shell short, stout, bicouic, white or subt ranslucent with a yellowish periostracum ; 

 apical whorls much eroded, indicating for the whole shell six or more turns ; suture 

 appressed, whorl iu front of it steeply descending to a very strong keel at the 



