PECULIAR STRUCTURE. 
237 
Only one beautifully striped pilot was observed ; the 
little creature swam round and round the vessel as if 
looking for its voracious companion. 
On removing the skin of the shark's head, a thick 
gelatinous-looking layer was seen, in which white 
nervous fibrillsc were particularly numerous. We could 
not but think of the possible truth of the views of 
some physiologists, who consider this structure to be 
endowed with the especial sensibility by which the 
shark is enabled to detect the course of ships, and 
to follow for a long time and distance in their 
wake. 
Certainly nothing seems better adapted than this 
jelly-like layer for conducting the impressions occa- 
sioned by the displacement and irregular action 
of water, during the passage of large bodies through 
it. Possessed of this conformation, it is not un- 
reasonable to suppose that a shark, crossing the 
track of a ship, might thus discover by the peculiar 
motion of the water, the course the vessel is 
taking. It is only by some such means we can ac- 
count for these monsters following as they often do, 
ships, which by their superior fleetness in a strong 
breeze, must have left them far, far astern; and yet 
on the first calm, they make their appearance perhaps 
to be captured, with proofs of their identity inside, 
in the shape of bones, clothes, &c., which had been 
throw overboard many days previously. 
This view, is certainly not more inconsistent than 
