161 
by the former mark. A large specimen of this last named 
species was taken in the Mount’s bay, and is well pre- 
served in the museum of the Society for Natural History 
at Penzance. From an examination of this I derive the 
following description: length three feet two and a half 
inches; extreme breadth two feet three inches; the margin 
much rounded, and expanding much more than in either ot 
Mr. Yarrell’s figures. Mouth narrow.and apparently feeble, 
the under jaw curved forward in the shape ot a horse shoe ; 
teeth small and sharp; temporal spiracles with an even 
continuous border. Colour of the upper surface deep brown, 
the skin smooth, sprinkled with small shot-like spots having 
some approach to regularity of distribution. The posterior 
lobe of the body has a regular fin with nineteen rays, ot 
which three at the two extremities singlo, the others double. 
Of the two dorsal fins the anterior is partly on the lower lobe 
of the body, two inches and a halt long, two inches and 
three quarters high; the distance between them two inches 
and three eighths. Second dorsal one inch and a hair long, 
two inches high ; from which to the caudal tin, two inches 
and a half. Eyes small, two inches and three eighths apart. 
Mr. Dillwyn ( History of Swansea, p. 61,) describes a spe- 
cimen clearly similar to the above, that measured in length 
forty-two inches, thirty inches wide, and weighed forty-three 
and a half pounds, and an observation of that gentleman on his 
specimen before and after it was set up lor preservation, will 
explain much of the discrepancy observed in the descriptions 
and figures of these fishes given by different authors. With 
the utmost care that was employed, the specimen, between 
the time of its death and preservation was found to have 
stretched from forty-two to forty-nine inches in length, and 
to have diminished in breadth iron thirty inches, to twenty- 
four, a circumstance which will explain the dispropor- 
tionate dimensions of Iiisso’s figures, and the want ot ex- 
pansion in even the British engravings. Ihe specimen at 
Penzance had been measured previously to setting up; and 
it is now fixed on a board suited to ils natural figure. 
SQUALIDiE. SHARKS. 
HAMMERHEAD. Squalus zygoma. Linnmus. ) Risso, 
Ichthyologie, p. 34. Zygasna malleus, Jenyns Man., 
p. 507. Yarrcll’s Br. F., vol. 2, p. 504. 
More than a single specimen ot this curious and voracious 
Shark, have been taken in Cornwall; but the only one pre- 
served, is in a dissected state in the museum ot Natural 
History at Penzance. 
