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CHAPTER XVI. 
Plate XXXI. — the chameleon, and intestine or the 
SEA-FOX. 
Fig. 1 . The chameleon , drawn from one of the species preserved 
in the Anatomy School, Christ Church, Oxford. The eyes of this 
creature are very peculiar: they are remarkably large, and project 
more than half their diameter. They are covered with a single 
eye-lid, with a small opening in it opposite the pupil. The eye-lid is 
granulated like every part of the surface of the body, with this differ¬ 
ence, over the eye the granulations are disposed in concentric circles 
which form folds in that part to which the eye is turned: and as 
the lid is attached to the front of the eye, so it follows all its move¬ 
ments. The neck is not “inflexible,” but its shortness, and the 
structure of the cervical vertebrae exceedingly limit the motion; 
this, however, is admirably compensated by the not less singular 
local position than motion of the eye, as the animal can see behind, 
before, or on either side, without turning the head. 
Fig. 2. The spiral intestine of the sea-fox cut open; taken from 
a preparation in the museum of the Royal College of Surgeons, 
London. The sea-fox is not, as Paley supposes, a “ quadruped ; ” 
but a species of shark, (squalus vulpes.) The convoluted intestinal 
tube is also found in some other genera of fish. In this specimen 
the internal membrane is converted into a spiral valve, having 
thirty-six coils; so that the alimentary substances, instead of passing 
speedily away, by proceeding round the turns of the valve, traverse 
a very considerable circuit: an extensive surface for the absorbents 
is thus provided. 
Fig. 3. The spiral valve removed, showing the mode of its 
coiling. 
