186 
MARINE SHELLS OF WEST COAST OF NORTH AMERICA 
This species was described from a young shell dredged by Dr. Ken- 
nerley, and only a quarter of an inch (6 mm.) in height. It has long 
remained unique, but of late years the U.S. Fish Commission and the 
Seaside Laboratory of the University of California at San Pedro have 
obtained adult specimens which reach a height of 28 mm. and a width 
of 26 mm. The adolescent shell has the apical whorls rose color, the rest 
yellowish-white, with the alternate spirals stronger, and articulated with 
madder brown both on the spire and the base. As the shell gets fully adult 
the color becomes less lively and the articulation less distinct, so that the 
general tone of the shell appears to be of a yellowish pink with indications 
of the nacre shining through. (Dali.) 
Type in United States National Museum, No. 122567. Type locality, 
Puget Sound, Washington. 
Range. Puget Sound to Cerros Island. 
Described as C. (annulatum var.) variegatnm Carpenter. 
Calliostoma platinum Dali, 1889 
Proceedings of the United States National Museum, 12:343; Pi. 7, fig. 2. 
Shell large, thin, polished, iridescent white, with seven whorls beside 
the nucleus; nucleus minute, lost; subsequent whorls slightly flattened 
behind the periphery, full and rounded on the base; longitudinal sculp¬ 
ture of obscure spiral lines behind the periphery and somewhat stronger 
flattish threads, separated by shallow grooves, on the base; at the periphery 
is a single prominent thread, immediately in front of which is the suture, 
the succeeding whorl being appressed against the thread; the single speci¬ 
men obtained has a second prominent thread about two millimeters behind 
the peripheral one. on the last whorl, but it is probable that the develop¬ 
ment of this thread was stimulated by an injury of which traces are plainly 
visible just before the second thread begins; base full and rounded; aper¬ 
ture rounded quadrate; the outer lip thin and sharp, its plane oblique and 
slightly flexuous; body with a very faint wash of callus; pillar slender, 
pearly, slightly arched, very little reflected, simple; interior polished, iri¬ 
descent, without lirae; the external sculpture faintly perceptible owing to 
the tenuity of the shell. Max. longitude of shell, 32; maximum latitude, 
29 mm. 
Type in United States National Museum. Type locality, U.S.S. “Alba¬ 
tross” Station 2839, near the Santa Barbara Islands, California, in 414 
fathoms, sand. 
Range. Farallon Islands to San Diego, California, in deep water. 
[ 788 ] 
