STRUTHIO CAMELUS. 297 



face for walking on \ It has a nail on the outer or little toe. A liga- 

 mentous elastic suhstance lies between the skin of the toe and tendon, 

 serving as a kind of cushion 2 . 



Both eyelids move equally, and both have muscles. The ligamentous 

 substance that connects the eyelid to the brim of the orbit all round is 

 very strong and distinct ; strong at its attachment to the orbit, beco- 

 ming thinner, and is at last lost insensibly in the lid. There is but one 

 tarsal cartilage, which belongs to the under eyelid, and is not near the 

 breadth of the eyelid ; it is a round piece of cartilage about the big- 

 ness of a halfpenny, situated in the middle of the lid, not coming close 

 to the edge of the eyelid, so that the remainder of this lid and the 

 the upper lid is membranous 3 . I could not find any Meibomian glands, 

 nor their openings. The muscles of the eyelids are three : two to 

 the upper, and one to the lower lid. The first of the upper is an 

 uncommon one : it is a thin muscle situated above the outer part of the 

 upper eyelid, under the ligamentous substance that connects it to the 

 orbit : it arises from the brim of the orbit a little on its inside ; thence 

 passes downwards and outwards, and is lost in the upper eyelid near 

 the external or posterior angle, and into the angle itself. The use of 

 this must be to raise the upper eyelid and at the same time to raise the 

 angle, which will affect the under eyelid, so that it might be called 

 ' levator communis.' What may be called ' levator proprius ' is nearly 

 as in the human subject, but is much broader; and part of its origin is 

 from the globe of the eye ; so that its action cannot be so much as the 

 others. The depressor is just such another as the levator; it arises 

 from the bottom of the orbit. The glands of the eyelids are two. 

 One [the Harderian] is placed just at the external angle of the orbit, 

 half within the bone, half without : it is about the size of the human 

 lacrymal gland, and much of the same shape and consistence ; it has a 

 large duct passing towards the external angle of the eyelids, where it 

 opens by a large orifice through the tunica conjunctiva, about half-way 

 between the angle or edge of the lid and the reflection of the tunic 

 upon the eyeball: the juice of this gland is of a brown colour, and 

 pretty thick. Qu. Whether or not this supplies the place of the juice 

 secreted from the Meibomian glands ? 



The other gland is placed on the under side of the eye lying imme- 

 diately between the depressor and the adductor muscles of the eye, 

 between them and the inferior oblique ; it is larger than the other gland, 

 and its juice is like water. From the anterior or outer end passes a 



[Hunt. Preps. Nos. 1902—1906.] 2 [lb. Nos. 274—276.] 



[lb. Nos. 1794, 1795.] 



