334 BULLETIN: MUSEUM OF COMPARATIVE ZOOLOGY. 



> Cepatia Gray, Syn. Brit. Mus., 1840; ibid., 1844, p. 60; P. Z. S. Lond., 1847, 



p. 149 ; N. cepacea Lamarck, Eocene. 

 Velainia Munier-Chalmas, Annal. de Malac, 1884, 1, p. 335 (= Cepatia Gray). 



> Naticina Fischer, Man. de Conchyl., 1885, p. 766, not of Guilding, 1834. 



> Sigaretopsis Cossniann, Cat. Illustr., 1888, 3, p. 172 ; type, N. in/undibulum Wat. 



Eocene (section of Cepatia). 



Polinices in the •wide sense, as the oldest available name, includes all the La- 

 marckiau Naticas with a horny operculum. In considering the subdivisions it 

 appears that Euspira Agassiz, which has five years' priority, notwithstanding some 

 discrepancies in the diagnosis, will have to be used in place of the more familiar 

 Lunatia of Gray. 



Polinices uber Valenciennes, var. inteinerata Philippi. 



Natica uber Val., in Humboldt, Geol. Obs., 1833, 2, p. 266. 



Natica'inlemerata Philippi, P. Z. S. Lond., 1851, p. 233; Tryon, Man., 1886, 8, 

 p. 46, pi. 18, fig. 83. 



U. S. S. " Albatross," station 3355, Gulf of Panama, in 182 fathoms, mud, 

 temperature 54!°.l F. U. S. N. Mus. 123,043. Also at Mazatlan, Mexico, and 

 living in Panama Bay, at station 2805, in 51 fathoms. 



Tryon and Carpenter regard this as probably a variety of P. uber, but the 

 specimens I have seen seem sufficiently constant to be rated as a good species. 



Polinices (Euspira) agujanu3 Dall, n. ep. 



Plate 9, fierure 2. 



Shell of moderate size, rather heavy, with five whorls, translucent white, with 

 an olivaceous periostracum; suture distinct, very minutely channelled; nucleus 

 eroded, whorls llattish in front of the suture, with a high, rounded shoulder and 

 evenly rotund body ; surface smooth except for faint, incremental lines, and, 

 under the lens, obscure spiral markings; base rounded, with a wide, deep, sub- 

 cyliudric umbilicus ; aperture semilunar, outer lip thin, simple ; the sutural 

 angle and the anterior part of the pillar-lip callous, a thin wash of callus on the 

 body ; operculum brown, horny, of two whorls. Alt. of shell, 26 ; of last whorl, 

 23; of aperture, 20; max. diain. 24 mm. 



U. S. S. "Albatross," station 4G53, 17 miles N. Gl° "W. from Aguja Point, 

 Peru, in 536 fathoms, mud, bottom temperature 41°.3 F. U. S. N. Miis. 110,566. 



The chief peculiarities of this species are the very minute channelling of the 

 suture, the fiat-topped whorls, and the singular want of callus on the thin, straight 

 pillar- The last character may perhaps be altered when the shell is older, though 

 otlierwisc our specimen seems fully adult. A di-ad and worn specimen, probably 

 of this species, was dredged at station 3360, Gulf of Panama, in 1672 fathoms, 

 sand, bottom temperature 42°. F. 



