MUSEUM OF COMPARATIVE ZOOLOGY. 117 



Mangilia scipio n. s. 



Plate X. Fig. 18. 



Shell extremely slender, thin, white, with nine or ten delicately rounded 

 whorls ; transverse sculpture consisting only of the delicate yet evident lines 

 of growth ; nucleus very small, not differentiated from the rest of the shell by 

 color or texture; three nuclear whorls marked by a distinct, apparently finely 

 serrate equatorial carina, which soon becomes obsolete; fasciole slightly con- 

 cave, smooth, except for lines of growth ; remainder of whorl covered with 

 fine slightly raised spiral threads separated by nearly equal interspaces and 

 continued to the anterior end of the canal; last whorl more than half the 

 length of the shell ; aperture simple, the notch broad, not very deep, and lying 

 upon the preceding whorl ; outer lip moderately arched forward, simple ; col- 

 umella hardly washed with callus; canal rather narrow and unusually long; 

 Lon. of shell, 14.0; of last whorl, 8.0 ; max. lat. of shell, 3.2 mm. 



Habitat. Station 269, off St. Vincent, in 124 fms., bottom temperature 57°.5. 

 Station 180, near Dominica, in 982 fms., ooze, temperature 39°.5 F. 



This is a remarkably delicate and singular shell ; the mouth being broken, the 

 characters of the lip were made out from the lines of growth. It is not like 

 any other species known to me. The nearest relative seems to be Daphnella 

 monoceros Watson, which is much larger and less attenuated in proportion to 

 its size. The long narrow canal of the present species forbids its reference to 

 Daphnella, and it is not improbably related nearly to the Pleurotomella group, 

 and to M. pelagia Dall. 



Mangilia pelagia Dall. 



Plate XI. Fig. 9. 

 Pleurotoma (Mangilia) pelagia Dall, Bull. M. C. Z , IX. p. 61, August, 1881. 



Habitat. Station 44, 539 fms., Gulf of Mexico, bottom temperature 39°.5 F. 

 There seems to be no described species at all nearly related to this one. 



Mangilia? exsculpta Watson. 



Plate XV. Fig. 9. 



Pleurotoma (Drillia) exsculpta Watson, Journ. Linn. Soc., XVI. p. 247, March, 1882. 

 Clionella exsculpta Watson, Chall. Gastr., p. 371, pi. xxiv. fig. 2, 1885. 



Habitat. Yucatan Strait, 640 fms., fragment. Station 134, near Santa 

 Cruz, in 248 fms., coarse sand, temperature, 54°. 5 F Challenger Expedition, 

 390 fms., ooze, north of Culebra Island, West Indies. 



The nucleus of this species is white, glassy, globular and nearly smooth, 

 composed of about two whorls, not swollen beyond the size of those that follow 



