116 American Se ash ells 



Calliostoma variegatum Carpenter Variable Top-shell 



Figure 33b 

 Alaska to southern California. 



I inch in length, similar to doliarium, but with smaller cords which are 

 strongly beaded; nucleus pink; the sides of the spire slightly concave, and 

 the periphery of the last whorl rounded. Uncommonly dredged in 15 to 

 400 fathoms. 



Calliostoma gloriosmn Dall Glorious Top-shell 



Figure 33a 



San Francisco to San Diego, California. 



I inch in length, not quite so wide, rather light, with about i o fine, spiral 

 threads between sutures. The upper 5 are inclined to be minutely beaded. 

 Periphery of last whorl moderately sharp. Columella white, fairly thick and 

 with a swelling at the lower %. Nuclear whorls white. Color of shell yellow- 

 ish brown with darker purplish brown, slanting and rather elongate spots 

 arranged in 2 spiral series. Moderately common in shallow water. 



Calliostoma splendens Carpenter Splendid Top-shell 



Figure 33c 



Monterey to Lower California. 



/4 to H inch in length, equally wide, with about 5 to 6 whorls which 

 bear between sutures 5 strong spiral cords. The upper 2 or 3 arc finely 

 beaded, the lower 2 or 3 are smooth and cord-like. Between the cords, the 

 shell is brilliant orange-iridescent. General color a yellowish orange with 

 large white maculations on the upper half of the whorls. Moderately com- 

 mon offshore, uncommonly washed ashore. 



Calliosto777a ligatum Gould Ribbed Top-shell 



Figure 33g 



Alaska to San Diego, California. 



% to I inch in length, equally wide, rather heavy; whorls quite well 

 rounded; characterized by smooth, spiral, light-tan cords (6 to 8 on the spire 

 whorls) on a background of chocolate. Sometimes flushed with mauve. No 

 umbilicus. Aperture usually pearly-white. A very common littoral species 

 from northern California north. Formerly C. costatuin Martyn. 



Subfamily GIBBULINAE 

 Genus Livona Gray 1847 



There is only one species this genus, namely L. pica from the West 



