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! vessel through the water must be deducted from 
f the force exerted by the powerful animal. The 
j weapon in this case had penetrated through one 
j inch of sheathing, three inches of planking, and 
four inches and a half of the solid timber. 
The Sword-fish is the furious enemy of the 
Whales, including the northern species and the 
Cachalot ; and many accounts relate the rage and 
I energy with which the armed warrior of the 
seas attacks his gigantic foe, and seeks to bury 
j his weapon in his mighty sides. And in this 
I animosity a motive has been sought for the sui- 
cidal assaults already mentioned, the Sword-fish 
I mistaking the hull of the ship, a huge dark body 
i moving through the water, for his enemy, and 
I darting upon it with blind indiscriminating fury. 
I It may be so : but Cuvier mentions a little fact, 
with which these attacks may not be unconnected. 
Notwithstanding its formidable weapon, its 
great strength, and its almost incredible celerity, 
a small crustaceous animal penetrates the flesh of 
the Sword-fish, and sometimes so torments it that 
it dashes itself on the shore with mortal violence.” 
3. Centronotina, The form is oblong, or some- 
times lengthened and slender ; the fore part of 
the dorsal is superseded by a number of small 
free spines ; the ventrals are present and perfect ; 
the body is covered with very small scales. Seventy 
species are reckoned to belong to this group, 
which ranges over all seas. The most worthy of 
notice is the beautiful little Pilot-fish {Naucrates 
ductor^ Linn.), so called because of its constant 
attendance on Sharks, as well as on ships, a pro- 
pensity as unaccountable as it is interesting. The 
fact is indubitable ; we have ourselves witnessed 
