230 WEST AMERICAN SHELLS 
Lamellaria stearnsi, Dall, Stearn’s 
Lamellaria, Figure 251. This little shell 
is rather poorly represented in Figure 
Fig-251 251. It is pure white, very thin, and has 
so large an aperture that the interior of the shell 
is plainly visible. During the life of the animal 
the shell is wholly covered and concealed by the 
white, translucent, soft parts of the living creature. 
In Lamellaria diegoénsis, Dall, the San Diego 
Lamellaria, the soft parts are bright red in color, 
and the little shell is 17mm. in diameter. 
The west coast of America abounds in limpets. 
Some species cling to rocks which are seldom cov- 
ered, others live half of their lives under water, 
while a few must be sought at very low tide. Their 
dead shells are very common objects along the 
coast, for they are lable to fall victims to some 
wandering crab, if they become washed from their 
footing. Though they creep around somewhat 
they usually return to the same spot to roost, and 
the protecting shell is seldom lifted to any con- 
siderable distance above the object to which they 
cling, and when at all disturbed they close it down 
with force and rapidity. In an especial manner 
these helpless animals must depend on their thick, 
hard shell to protect them from injury. 
Acmea spéctrum, Nutt., the 
Ribbed Limpet, lives far up on 
the rocks, where it receives 
only a few splashings at high 
tide. It is gray in color, much 
like the granite to which it 
Fig. 252 
