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of muscular fibres deposited in its centre. The conjunctiva of the lids 

 is highly vascular, injected with blood, and covered with orifices of 

 mucous duets. At the inner canthus of the eye it fonns a thick 

 duplicature, of crescentic form, constituting a rudimentai third eye- 

 lid, not unlike the ha\v of the horse. The globė of the eye is chiefly 

 lodged in the soft parts, but little if any of its substance entering 

 the bony orbit. It is deeply set \vithin the lids, and does not in size 

 much exceed that of an ox. Its size in aii adult female ^vas 2^ inches 

 in the longitudinal, and the šame in the vertical direction. The in- 

 terior or cavity "tt'as lį inch in each of the last-named directions, and 

 its depth §rds of an inch only. 



" The globa at its greatest circumference was 7į inches : the trans- 

 parent cornea at its transverse or broadest diameter measured 1 inch, 

 and in its vertical or narrowest įths of an inch. The museles of the 

 globė formed a dense mass surrounding the sheath of the optic nerve, 

 and were inserted in one continuous line over the circumference of 

 the globė at its greatest convexity. 



" The optic nerve before penetrating the sclerotic is continued to 

 some length. It does not exceed the circumference of a crow's quill, 

 but is surrounded by a dense fibrous sheath nearly 4 inches in peri- 

 meter, and which, where the nerve perforates the globė, terminates 

 on the posterior surface of the latter. Around the globė and its 

 museles much cellular tissue and true fat are deposited. The eyebaU 

 in shape is not a perfect sphere ; its anterior and posterior surfaces 

 are flattened : that portion of the conjunctiva of the globė immediately 

 surrounding the cornea, and the only portion exposed betvveen the 

 aperture of the lids, is of an intense black hue. It is possible this 

 dark portion may be a membrane distinct from the conjunctiva, since 

 around the extent it occupies, it terminates by an irregular margin, 

 and is capable of being detached from the conjunctiva, when it presents 

 the form of a dehcate layer of cuticle, with a black pigment deposited 

 beneath its surface*. 



" The cornea of the Cachalot is dense, and composed of many 

 layers ; ■vvhen divided, a small ąuantity of limpid aqueous humour 

 flows forth : the anterior chamber of the eye is very limited, and the 

 crystalline lens projects into it through the pupillary aperture. The 

 iris is a coarse membrane of a dull-brown colour, vrith a narrow zone 

 of lighter hue surrounding its outer margin. Its inner and free margin 

 is very thin, and embraces the protruding convexity of the lens. 



"The lens is small, certainlynot exceeding in size that of the human 

 eye : it forms nearly a perfect sphere : the vitreous humour tolerably 

 abundant. The retina was spread with beautifully dehcate arbo- 

 rescent vessels, and afforded a small bright spot at the insertion of 

 the optic nerve. Beneath the retina was spread a tapetum of dense 

 membranous texture, and yellow-green or erugo-green colour. The 

 sclerotic at its posterior third is thick, fibrous, and resisting, \vhilst 

 its anterior third is thin and flexible ; no lachrymal apparatus 

 exists." 



* A sHght dark tint around the cornea is not uncommon amongst the 

 dark-skinned natives of \varm countries. 



