Bon BULLETIN: MUSEUM OF COMPARATIVE ZOOLOGY. 
Hipponix serrata Carpenter. 
Hipponyzx serratus Carpenter, Maz. Cat., 1856, p. 296. 
U.S. 8S. “Albatross,” station 2798, in Panama Bay, in 18 fathoms, Mazat- 
lan, Reigen. U.S. N. Mus. 110,654. 
Naticidae. 
NATWTEICA Scoro.t. 
Natica Scopoli, Intr. Hist. Nat., 1777, p. 392 (after Adanson); type, NV. vitellus 
(Linné) ; Lamarck, Prodr., 1799, p. 77; sole ex., N. canrena Linné. 
The forms with calcareous opercula having been indicated by Lamarck as typi- 
cal, we may, as I have indicated in my Report on the Oregon Miocene, subdivide 
the group in part as follows : 
Natica s. 8. Umbilicus open, with a spiral ridge internally ; operculum externally 
spirally multisulcate. LV. vitellus Linné. 
Cochlis Bolten, 1798. Umbilicus similar to that of Natica s.s. Operculum with a 
very few, or only a single marginal sulcus. JV. spadicea Gmelin. 
Cryptonatica Dall, 1892. Operculum smooth, without spiral sulci, umbilicus com- 
pletely closed with a smooth pad of callus. NV. clausa Brod. and Sowerby. 
The first and second groups are tropical or subtropical ; the last is cool-temper- 
ate or arctic. There are several other groups, such as Nacca, Stigmaulax, and 
Payreaudeautia, but these are not represented in the present collection. 
Natica (Cochlis) othello Da tt, n. sp. 
Shell rather thin, elevated, with a rather pointed spire of four and a half whorls 
of which four are nuclear, smooth, and brownish, the remainder buff, very pale 
brown, or grayish-white, with a polished surface; suture very distinct, not chan- 
nelled or appressed ; periostracum dehiscent, chaffy, pale yellowish-brown; an 
obscurely defined whitish band in front of the suture and at the base ; axial sculp- 
ture of sharply incised, numerous retractive lines, forming a halo in front of the 
suture and behind the shoulder of the whorl; there are about two or three of 
these radii to the millimeter and they average about four millimeters long on the 
last whorl, with wider, radially striated interspaces ; the remainder of the whorl is 
smooth, except for faint incremental lines, and more or less obscure, obsolete, 
spiral striation ; umbilicus narrow, with a nearly vertical, strong spiral internal 
rib, nearer the anterior wall of the umbilicus; aperture oval, outer lip sharp, thin; 
body with a moderate white callus, interrupted in front by the umbilicus; pillar 
white, throat livid flesh-color; operculum shelly, of two and a half whorls, inter- 
nally smooth and slightly convex, externally flattish, apically depressed, white, with 
