CHITONS. 
33 
being detached, they instantly become alarmed, the 
shelly valves bend more downward, the leathery 
mantle clings to the surface, and the muscular adhe- 
sion of the foot becomes so great that no force can 
now detach the animal, short of that which would 
destroy the specimen. The approved mode of pro- 
ceeding is as follows. Tate an old rounded table- 
knife, with which the collector should be provided, 
in the left hand, so that the tip of the blade shall be 
close to one extremity of the Chiton^ without touch- 
ing it. Then, with the palm of the other hand, as a 
mallet, give a smart blow to the handle, the effect of 
which will be that the animal is pushed from its hold 
before it has time to be alarmed. In the present 
case, however, this device was impracticable ; for, 
owing to the very carious surface of the rock, and the 
Chitons generally filling a hollow, it was impossible 
to push them off. But I found that by suddenly 
inserting the dull point of a strong pocket-knife 
under the margin of the mantle, and giving a quick 
wrench, I could remove them with facility, and gene- 
rally without cutting or tearing the edge. Out of 
more than fifty specimens which I essayed, I did not 
lose more than two or three. Yet the operation was 
not without difficulty, from the very sharp projec- 
tions of the rock, and the force of the surf, which 
frequently dashed violently over my head, and once 
or twice knocked me down. I had to catch the 
momentary intervals of the waves, to dislodge my 
booty ; and sometimes a sea coming at the moment 
I had done it, washed it from my grasp. The finest 
specimens were found on the seaward side, and on the 
