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XXX (292) XXX

292 A N A T O M Y. ‘ Part VI. The broad UgamentS'Of the tarfi are membranous e- They are the orifices of the fame number of fmall oblong glands which lie in the fulei, channels, or ^groove? I o -gatioHS formed by the union of the peri oft sum of the furface of the tarfus. Thefe little glands t-rbits ' and pericranium along both edges of each orbit. onare theof inner a whitilh colour; and when fqueezed, a febaThe fuperior ligament is broader than the inferior, and fixed to the fupetior edge of the upper cartilage, as the ceous matter like foft wax, is difcharged through the inferior is to the lower edge of the lower cartilage, fo punCta ciliariu. that thefe ligaments and the tarfi, taken alone or without Near the great or internal angle of the palpebne, the flat portion of their edges terminates in another which is the other parts, reprefent palpebrse. The membrana conjunftiva is a thin membrane, one rounder and thinner. By the union of thefe two edges portion of which lines the inner furface of the palpebras. an angle is formed. At the edge of the orbit it has a fold, and is continued At this place, the extremity of the flat portion is difrom hence on the anterior half of the globe of the eye, ftinguilhed from the round portion'by a fmkll protube-, adhering to the tunica-albuginea; fo that the palpebrce ranee or papilla, which is obliquely perforated by a fmall and the forepart of the globe of the eye are covered by hole in the edge of each palpebra. Thefe two fmaH one and the fame membrane, which does not appear to holes are very vifible, and often more fo in living than be a continuation of the pericranium, but has fome connec- in dead bodies, and they are commonly named puntia lachrymalia, being the orifices of two fmall dudts which tion with the broad ligaments of the tarfi. The name of conjunttiva is commonly given only to open beyond the angle of the eye into a particular referthat part which covers the globe, the other being called •voir, termed facculus lachrymalis, which lhall be delimply the internal metnbrane of the palpebrse ; bnt we feribed in the article of the nofe. may very well name the one membrana oculi conjunc- The pun&a lachrymalia are oppofite to each other, and tivaand the other metnbrana palpebrarum conjunftha. fo they meet when the eye is flmt. Round the orifice of That of the palpebrae is a very fine membrane adhering each of thefe points, we obferve a whitilh circle which to be a cartilaginous appendix of the tarfus, and very clofe, and full of-fmail capillary blood-vefiels. It is feems “perforated by numerous imperceptible pores, through which keeps the orifice always open. The caruncula lachrymalis is a fmall reddiih, granuwhich a kind of ferum is continually difcharged. The conjunctiva of the eye adheres by the interven- lated, oblong body, fituated precifely between the intertion of a cellular fubftance, and is confequently loofe, nal angle of the palpebrse and globe of the eye. The of it feems to be wholly glandular. We difand as it were moveable; and it may be taken hold of and fubftance Separated in feveral places from the tendinous coat. It cover upon it a great number of fine hairs covered by an oily, yellowilh matter; and on the globe of the eye, is of a whitilh colour; and being tranfparent, the albu- near this glandular body, we fee a femilunar fold, formginea makes it appear perfectly white: Thefe two coats together forming what is called the white of the eye. ed by the conjundtiva, the concave fide of which is turn The lachrymal gland is white, and of the number of ed to the uvea, and the convex fide to the nofe. thofe called conglomerate glands. It lies under thatdepreflion obfervable in the arch of the orbit near the temThe Muscles of the Palpebrje. ples, and laterally above the globe of the eye. It is a The mufcles the palpebrse are commonly reckonIhtle flatted, and divided as it were into two lobes, one ed to be two, oneofpeculiar to the upper eye-lid, named of which lies toward the infertion of the mufculus reCtus palpebne fuperioris ; the other common to both, fuperior, the other toward the reCtus externus. It ad- levator orbicularis palpebrarum. heres very clofely to the fat which furrounds the mufcles- called The levator palpebrse fuperioris Is a very thin mufcle,and pefterior convexity of the eye, and it was formerly fituated in the orbit above, and along the redius fuperior named glandula innominata. From this gland feveral fmall.duCls go out, which run oculi. It is fixed to the bottom of the orbit, by a finall narrow tendon, near the foramen opticum, between the down almoft parallel to each other, through the fub- pofterior of the redlus fuperior and obliquus ftance of the tunica interna or conjunctiva of the fuperior fuperior. infertions From thence its flefiiy fibres run forward on palpebra, and afterwards pierce it inwardly near the futhe redtus, increafing gradually in breadth, and termiperior edge of the tarfiis. The flat edge of each palpebra is adorned with a row nate by a very broad aponeurofis in the tarfus of the fuof hairs called cilia, or the eye-lafhes. Thofe belong- perior palpebra. ing to the fuperior palpebra are bent upward, and longer By the mufculus palpebrarum obliquus we underftand than thofe of the lower palpebra which are bent down- all that; extent of ftefhy fibres, which by a thin ftratum furrounds the edge of each orbit, and from-thence, withward. rows aredouble placed ornexttriple. the Ikin,Theandhairs are not A burThefe irregularly are out any interruption, covers the two palpebrae all the way . - r rr the middle of the palpcbrte than toward the to the cilia. Almoft all of them have a common tendon , nd for about a quarter of an inch from the fituated tranfverfely between the internal angle of the iii .mgle ;Vy are quite wanting. eye- and the nafal apophyfis of the os maxillare. This herd: r of the palpebra-, near the inter- is a {lender Itgarnentary tendon, ftrongeft where it is ■:i , cj toward the eye, we fee a row of fmall fixed in the bone, and dimini/hing gradually as it ap■ A iv.mcd fc,~mina or punfl* ciliaria* proaches the angle of the palpebrae, where it terminatesat