CLASS GASTROPODA 
73 
subfugaci, laminis increment subrugosa; operculo pyriformi, haud angu- 
lato, apice antico. Long., 1.13; long, spir., 0.65; lat., 04. (Carpenter.) 
Shell in general form like C. ophiderma, but smaller, the whorls some¬ 
what more rounded; cinerous, with reddish chestnut revolving lines. 
(Tryon and Pilsbry, Manual of Conchology .) 
Spiral sculpture grooved, not raised. (Carpenter.) 
Type in? Type locality, Puget Sound. 
Range. Puget Sound to San Pedro, California. Fossil: Pleistocene— 
Santa Barbara, San Pedro, San Diego. 
Described as Drillia incisa Carpenter, 1856, not Pleurotoma incisa 
Reeve, 1843. 
Clathrodrillia incisa ophioderma Dali, 1908 
Proceedings of the United States National Museum, 34:247. Hinds, Zoology of the 
Voyage of H. M. S . Sulphur, Pi. 5, fig. 7. 
Pinkish ash-colored under a light olivaceous epidermis, the lines of 
growth, which are sometimes rib-like, oblique and angulated at the 
periphery and lighter-colored, so that the interspaces appear like angulated 
lines of chestnut or reddish narrow stripes; whole surface covered by 
close revolving incised lines. Length, 38; diameter, 13 mm. (Tryon, 
Manual of Conchology.) 
Type in? Type locality? 
Range. Baulinus Bay, California, to Ballenas Lagoon, Lower Cali¬ 
fornia. Fossil: Pleistocene—Santa Barbara, Ventura, San Pedro. 
A new name for Drillia inermis Hinds. 
Clathrodrillia halcyonis Dali, 1908 
Plate 7, fig. 2; Plate 18, fig. 1 
Proceedings of the United States National Museum, 34:248 ; 56: PI. 8, fig. 1, 1919. 
Shell small, slender, very acute, of a livid purple covered with an 
olivaceous periostracum, with about eleven whorls; nucleus more or less 
eroded, but apparently smooth, acute, and including about two and a half 
whorls; subsequent whorls rather flat, compressed and appressed at and 
in front of the suture, with a rounded base and inconspicuous anal 
fasciole; sculpture chiefly of flatfish spiral threads, one at the suture, 
three smaller ones in front of it, followed by a flat broader one represent¬ 
ing the fasciole, then (on the last whorl eight) more prominent threads, 
undulate or segmented by incremental lines and with wider interspaces 
(sometimes containing an intercalary smaller thread) to the base, followed 
by six or seven unsegmented threads to the siphonal fasciole, which bears 
six or seven smaller threads; the succession of undulations or slightly 
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