230 
MARINE SHELLS OF WEST COAST OF NORTH AMERICA 
Schismope caliana Dali, 1919 
Proceedings of the United States National Museum, 56:370. 
Shell minute, translucent white, of three whorls and a minute glassy 
subglobular nucleus; suture distinct, last whorl with a keel halfway to the 
periphery, another at the periphery; half a whorl back from the aperture 
between these two is the oval perforation found in the genus; these inter¬ 
spaces are wide; a third keel is found nearer the second on the outer part 
of the base, and several finer ones on the base, which is funnel-shaped in 
the center but forms merely a pit, the axis being imperforate; aperture 
wide, the upper part of the outer lip protracted; the pillar lip thin, arcu¬ 
ate, the general form of the aperture rounded. Height, 1; maximum 
diameter, 1.5 mm. (Dali.) 
Type in United States National Museum, No. 198609. Type locality, 
San Diego, California. 
Range. Known only from type locality. 
Family HALIOTIDAE 
Genus HALIOTIS Linnaeus, 1758 
The principal characters for distinguishing the species are the outline 
of the shell, which is either equally curved on the two sides or straighter 
on the right margin; the convexity of the back, which may be carinated 
or rounded at the row of holes; the sculpture; the position of the spire; 
the color of the inside; smoothness or roughness of the muscle-scar; width 
and slope of the columellar-plate; and, within rather wide limits, the 
number of open holes. It is convenient to segregate the numerous species 
of Haliotis into groups; and the following is offered as a preliminary 
arrangement. (Tryon and Pilsbry, Manual of Conchology.) 
First species, Haliotis midae. 
Distribution. West coast of North America, Alaska, Australia, Japan. 
Haliotis cracherodii Leach, 1817 
Zoological Miscellany, 131. Conchologia Iconica, fig. 23. 
H. supra caerulescente-niger, umbone laterali-dorsali; interne margari- 
taceus iricolor. 
Bluish-black above, umbo lateral-dorsal; internally pearly and irides¬ 
cent. (Leach.) 
Shell oval, convex, spire near the margin; surface almost smooth, but 
usually showing nearly obsolete spiral lirae. Perforations about eight, color 
greenish-black or dull purplish-black. 
[832 1 
