1918 | Packard: Molluscan Fauna from San Francisco Bay 311 
TROCHIDAE 
Calliostoma Swainson 
Calliostoma canaliculatum (Martyn) 
Plate 36, figure 5 
Calliostoma canaliculatum, Pilsbry (1889), p. 361, pl. 67, fig. 49; Wood and 
Raymond (1891), p. 57; Arnold, R. (1903), p. 329. 
Description—Pilsbry (1889) described this species as follows: 
**Conical with flat base, thin, light fawn colored with yellowish-white lirae; 
imperforate; surface of the whorls encircled by numerous sharply sculptured 
smooth, narrow, cord-like lirae, subequal or alternately smaller; base with 11 to 
13 similar ones. On the upper whorls the lirae are fewer, and in well preserved 
individuals the second whorl is minutely beaded above. Spire conic, with nearly 
straight outlines; sutures impressed. Whorls 7-8, the last obtusely angular, 
flat beneath and impressed around the axis. Aperture oblique, rhombic, iri- 
descent and suleated inside; peristome thin, acute; columella straightened, not 
truneate below, dilated in a pearly iridescent pad above, bounded by an opaque 
white deposit.’’ 
This common shell occurs quite abundantly along the shores out- 
side of the Golden Gate. It has been reported from this region by 
Wood and Raymond (1891). It was not obtained by the Survey. 
Range—Sitka, Alaska, to San Diego, California (Pilsbry). 
Calliostoma costatum (Martyn) 
Plate 36, figures 6 and 7 
Calliostoma costatum, Carpenter (1863), p. 652; Pilsbry (1889), p. 362, 
pl. 16, figs. 6, 9; pl. 18, fig. 16. 
Description.—This species was described by Pilsbry (1889) as follows: 
“*Shell conical, rounded at periphery, base flattened; imperforate; solid; 
dark chestnut colored, the spiral riblets lighter, apex dark, usually purple. 
Surface encircled by numerous spiral smooth riblets, their interstices closely 
finely obliquely striate; riblets usually 7 to 9 on the penultimate whorl, about 
9 on the base. Spire conic; apex acute; sutures impressed. Whorls about 7, 
convex, the last rounded (or a trifle angled) around the lower part, slightly 
convex beneath; aperture rounded, oblique, outer lip fluted within, with a 
beveled opaque white submargin; throat pearly, iridescent; columella simple, 
arcuate.’? 
Height, 9 to 11 mm. 
Occurrence.—At station D 5770* (2). 
Carpenter (1863) lists this species from the Farallon Islands. Two 
living specimens were dredged by the Survey near the north shore of 
the Golden Gate at a depth of 5 fathoms. The bottom at that locality 
is characterized as being stony. This species occurs abundantly along 
the beaches of the open ocean. 
Range.—Sitka, Alaska, to San Diego, California (Cooper). 
