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ON THE OCCURRENCE OF THE CENTRINE SHARK 
OFF THE COAST OF CORNWALL. 
By Tuomas CoRnisH. 
I HAVE recently obtained from a trawler a specimen of the 
Centrine Shark (Sguwalis centrina), the first, so far as I can 
ascertain, taken in English Seas. It was trawled up from a sandy 
bottom in twenty-six fathom water near the Wolf Lighthouse. It 
is at all events so rare a fish that I feel justified in giving you 
some account of it. 
The feature which at once distinguishes the fish from all other 
sharks which I have seen is the presence within the skin and 
through the centre of the two dorsal fins of a stout spine, the 
end of which projects beyond the fin. The spine of the first 
dorsal starts from the base of the horizontal middle of the fin and 
inclines forward; the spine of the second dorsal starts from about 
the same relative position and inclines backward; so that each fin 
is a complete spritsail with the sprit rigged. 
The length of my specimen is two feet one inch, over all (Bloch 
says the fish reaches a length of three or four feet). Its girth 
immediately before the pectorals, nine inches and four-eighths ; 
girth behind the first dorsal, twelve inches. The head is depressed 
and broad. The eyes are large and long, with bright green round 
pupils and no nictitating membrane; over them the orbit is a 
strong bony ridge, and immediately behind them are blow-holes. 
Behind them and in front of the pectorals are five very small gill- 
apertures. The lips are very white and very fleshy and entirely 
cover the teeth. Bloch apparently described his fish from a 
specimen dead long enough for the fleshy lips to have dried 
back. 
The mouth is very small. The teeth in the lower jaw are 
equilateral! and in two rows, the outer one consisting of much 
smaller take than the inner one. The teeth in the upper jaw are 
numerous and in irregular rows and sharp-pointed, and I think all 
of them are serrated, but they are all so small that I am not 
certain about this. The first dorsal stands just over the pectorals, 
and the second just over the ventrals, and each dorsal has through 
it the spine I have described, and is free at the rear of the base 
for about half an inch. The belly is broad and flat; the pectorals 
