PIERCED SHELLS AND CHITONS 255 
they are made into buttons, and used for various 
kinds of inlaid work. So persistent has been the 
warfare against this species that large specimens 
are much more rare than they were a score of 
years ago, and laws have been made to protect 
them from extinction. 
The Black 
Abalone, Halio- 
tis cracherodu, 
Leach, is shown 
in Figure 288. 
It is smaller and 
more abundant 
than the last 
species. The 
back is quite 
smooth, marked only by lines of growth. The 
spire is very short, the holes five to nine in 
number, and the color is greenish-black without 
and whitish-pearl-colored within. Live specimens, 
varying from one-fourth of an inch to six inches in 
length may be found at low tide, clinging to the 
rocks, particularly in the most inaccessible cracks, 
and under heavy boulders. 
When examined in a large jar of sea-water, as 
all of these animals should be if there is an oppor- 
tunity, a living specimen presents many inter- 
esting points for study, particularly its broad 
foot, its fringed and sensitive mantle, its mouth 
and eyes and slender tentacles. 
Haliotis corrugata, Gray, the Corrugated Aba- 
lone, represents H. rufescens in size and color, 
