DALL: MOLLUSCA AND BRACHIOPODA. 299 
TRACTOLIRA Datt. 
Tractolira Dall, Proc. U. S. Nat. Mus., 1896, 18, p. 12; Smithsonian Misc. Coll. 
Quarterly, Feb., 1907, 48, part 3, p. 365. 
Shell slender, drawn out in its coil, fusiform, with a short canal and pervious 
axis; outer lip simple, not expanded or lirate ; body not callous, the axis twisted, 
with a single strong plait at its anterior edge, the young showing five or more 
narrow, low, thread-like ridges behind the one above mentioned, but which become 
obsolete in the adult. 
This singular shell appears to be a degenerate abyssal form of Volutidae, but 
which can not be assigned to any of the genera yet established. 
Type 7. sparta, Dall. 
The fossil Voluta alta Sowerby, of the South American Tertiaries, has the aspect 
of being a precursor of 7. sparta. 
Tractolira sparta Datu. 
Plate 2, figure 7. 
Lractolira sparta Dall, Proc. U.S. Nat. Mus., 1896, 18, p. 13, Smithsonian Misc. 
Coll., 1907, 48, p. 366. 
Shell elongate, slender, with a greenish or ashy adherent epidermis (more or 
less eroded near the apex in all the specimens), and about six whorls; nucleus 
apparently as in Adelomelon, large, with an apical spur; whorls drawn out, rounded, 
with a distinct suture, the upper whorls at first smooth, then with irregular, 
partly obsolete, transverse wrinkles, some of which cross the whorl, but which 
are too irregular to call ribs; surface everywhere sculptured with numerous, 
even, fine, flattish spiral threads, with equal or slightly wider interspaces, and 
with well marked but not regular lines of growth; aperture subovate, rather wide 
in front, the outer lip simple and hardly thickened; the throat white, a thin wash 
of callus on the body, the pillar thin, pervious, short; the canal short and wide, 
with hardly any siphonal fasciole; operculum absent. Height of shell, 60; of 
last whorl, 43; of aperture, 28; diam. 19 mm. 
U.S. 8. “ Albatross,” stations 3360, 3374, 3414, and 3415, in 1672 to 2232 
fathoms, mud, bottom temperatures 35°.8 to 36°.4 F.; Gulf of Panama to Aca- 
pulco, Mexico. U.S. N. Mus. 122,999. 
This is a very characteristic and singular abyssal shell. 
Ptychatractidae. 
PTYCHATRACTUS Stimpson. 
Ptychatractus californicus Datt, n. sp. 
Shell small, fusiform, white, with a pale straw-colored periostracum and about 
five whorls ; suture distinct, not appressed, whorls turgidly rounded ; axial sculp- 
