No. 1610. NEW PACIFIC COAST MOLL USKS—DALL. 249 
brown small spots. Adults measure about 18 mm. in length and have 
the interior of the outer lip thickened and with six or seven well-— 
marked denticulations. 
Type.—Cat. No. 199893, U.S.N.M. 
Genus TRITONOFUSUS Beck. 
TRITONOFUSUS (PLICIFUSUS) KELSEYI, new species. 
Shell elongate, slender, acute, the spire much longer than the 
aperture; white, covered by an olivaceous periostracum; having ten 
whorls exclusive of the (eroded) nucleus of about two whorls; suture 
appressed and the whorls shghtly constricted in front of it; axial 
sculpture of (on the seventh whorl about 12) concavely arcuate, 
slightly protractive, low narrow ribs, crossing the whorls, on the later 
whorls becoming obsolete and finally absent from the last whorl alto- 
gether; the interspaces are wider than the ribs; these are crossed by 
fine sharp spiral striz, somewhat irregularly spaced, of which there 
are about a dozen on the seventh whorl, a narrow space before the 
suture being less sharply or not at all striate; aperture narrow, outer 
hp arcuate, somewhat excavated near the suture and produced an- 
teriorly, shghtly thickened, simple, and internally smooth; inner lip 
smooth, with the sculpture erased, passing gradually into the long 
straight pillar, which is attenuated in front; canal long, narrow, 
straight; length of shell 34.0; of last whorl 18.5; of aperture 14.5; 
maximum diameter 8 mm. 7 
Fossil in the Pleistocene of San Pedro, California, Eshnaur. 
Type.—Cat. No. 110631, U.S.N.M. Dredged-by the U.S. Fisheries 
steamer Albatross off San Diego in 124 to 359 fathoms, bottom tem- 
perature 49° F. (young specimens) ; dredged in 50 fathoms off San 
Diego, Prof. F. W. Kelsey (adult). 
This species is closely ‘related to 7’. rectirostris Carpenter, which is 
less slender, with more numerous and persistent ribs, and spiral 
threading instead of strize. The latter is also a larger shell when 
full grown. 
Genus BOREOTROPHON Fischer. 
(Neptunea Bolten.) 
BOREOTROPHON BENTLEYI, new species. 
Shell small, slender, acute, ashy white, with about seven whorls; 
nucleus with the surface eroded; suture distinct, the whorl in front 
of it somewhat tabulated by an obscure angle from which the spines 
arise; axial sculpture, besides incremental lines, only of about (on 
the last whorl) ten sharp depressed lamellar varices, prominent 
only behind the periphery and feeble on the base; at the shoulder 
these are produced into high, usually recurved, guttered spines, 
