SIX-GILLED SHARK. 
rs 
thus shewing a near correspondence with a like structure in 
the genus Pristiurus. The texture of the skin is rough when 
felt against the grain. Colour blackish brown on the back, and 
pectoral, dorsal, and caudal fins; reddish grey on the sides, 
white beneath. Lateral line pale, bent suddenly down at the 
falcate portion of the tail. Conjunctiva of the eye bluish white, 
the pupil large and black. It was a male — the claspers small. 
I he example here described was taken with a line, at the 
distance of about three miles from the land on the south coast 
of Cornwall, and at the time when it was caught appeared to 
be feeding on pilchards. In its habits it is undoubtedly a ground 
Shark, and like the others of that class— the Nurse and Rough 
Hounds— appears to want activity. The fisherman who caught 
this fish informed me that it scarcely moved after it was taken 
into the boat. Eisso says that in the Mediterranean it keeps 
in very deep water, but in some parts is not uncommon; but 
Sw'ainson never met with it during six years in which he 
resided in Sicily. It also appears to have been unknown to 
the older naturalists, and I have sought for it in vain in the 
works of Rondeletius, Gesner, Willoughby and Ray, Jonston 
and Euysch, who may be judged to represent the ichthyo- 
logical knowledge of their day. It was not known to Artedi, 
nor to LinnsBus so lately as at the publication of the tenth 
edition of his system; but is recognised in Turton’s translation 
of Gmelin’s edition of that work, under the scarcely appropriate 
name of Squalus grtseiis. It is there represented as growing 
to the length of two feet and a half; but although this diflhrs 
so little from the size of the Cornish specimen, it is clear, 
from the additional teeth specified by Turton, that the latter 
must have been a younger individual. An example, the first 
and only other that has been taken in Britain, was caught 
with a line off Ventnor, in the Isle of Wight, and measured 
little less than eleven feet in length; and Risso describes the 
fish in terms which can signify nothing less than these full 
proportions. In the specimen referred to by Turton there was 
only one row of teeth in the upper jaw, but there were many 
rows in the lower ; from which we may judge that it is about 
this period of its growth that the evolution of dentition 
begins to shew itself, and first in the lower jaw, Eisso 
assigns three rows of triangular sharp-pointed teeth to the 
