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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 ducts. At the inner canthus of the eye it forms a thick 

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

 lid, not unlike the haw of the horse. The globe 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 within the Uds, and does not in size 

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

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

 terior or cavity was l^ inch in each of the last-named directions, and 

 its depth f rds of an inch only. 



" The globe at its greatest circumference was 7| inches : the trans- 

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

 and in its vertical or narrowest f ths of an inch. The muscles of the 

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

 and were inserted in one continuous line over the circumference of 

 the globe 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 globe, terminates 

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

 muscles much cellular tissue and true fat are deposited. The eyeball 

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

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

 surrounding the cornea, and the only portion exposed between 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 delicate layer of cuticle, with a black pigment deposited 

 beneath its surface*. 



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

 layers ; when divided, a small quantity 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, with 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, certainly not 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 delicate 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, whilst 

 its anterior third is thin and flexible; no lachrymal apparatus 

 exists." 



* A slight dark tint around the covnea is not uncommon amongst the 

 dark-skinned natives of warm countries. 



