440 Mr. Hunter’s Obfervations on the 
rotic coat and the bottom of the eye not above an inch and 
a quarter. 
In the Piked Whale the fclerotic coat, at its pofierior part, 
is very thick : near the extreme of the fhort axis it was 
half an inch, and at the long axis one-eighth of an inch 
thick. In the Bottle-nofe Whale, the extreme of the fhort 
axis was half an inch thick, and the extremes of the long axis 
about a quarter of an inch, or half the other. 
The fclerotic coat becomes thinner as it approaches to its 
union with the cornea, where it is thin and foft. It is extremely 
firm in its texture, where thick, and from a t ran fiver fe fecdon 
would l'eem to be compofed of tendinous fibres, intermixed 
with fomething like cartilage ; in this feciion four paffages for 
vefiTels remain open. This firmnefs of texture precludes all 
effect of the ftraight mlifcles on the globe of the eye, by alter- 
ing its fhape, and adapting its focus to different difiances of 
objects, as has been fuppofed to be the cafe in the human eye. 
The cornea makes rather a longer ellipfis than the ball of the 
eye ; the hides of which are not equally curved, the upper 
being mofi confiderably fo. It is a fegment of a circle fomewhat 
fmaller than that of the eyeball, is foft and very flaccid. 
The tunica choroides refembles that of the quadruped ; and 
its inner furface is of a filver hue, without any nigrum pig- 
men turn. 
The nigrum pigmentum only covers the ciliary procefles, 
and lines the infide of the iris. 
The retina appears to be nearly fimilar to that of the qua- 
druped. 
The arteries going to the coats of the eye form a plexus 
paffiug round the optic nerve, refembling, in its appearance, that 
of the fpermatic artery in the Bull and fome other animals. 
The 
