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 Part I. ANA T O M Y. 159 The third hole is formed between the bafe of this they run dmde4 within .the fltull.—Between that third protuberance and the pofterior clinoid proceis, the larger bone and the root of the orbitar procefs of the palatepit for the glandula pituitaria may be remarked. This bone of each fide. Through this a branch of the extercavity, becaufe of its refemblance to a Turkifh faddle, nal carotid artery, and of the fecond branch of the fifth is always defcribed under the name of fella Turcica, or pair of nerves, are allowed a paflage to the noftrils, and ephippium. On the fides of the pofterior clinoid pro- a returning vein accompanies them. cefs a fofia may be remarked, that ftretches upwards, Under the fella Turcica, and fome way farther forthen is continued forwards along the fides of the fella ward, but within the fubftance of the fphenoid bone, are Turcica, near to the anterior clinoid procefl'es, where a two finufes, feparated by a bony plate. Each of them pit on each fids is made. Thefe fo/fe point out the is lined with a membrane, and opens into the upper and courfe of the two internal carotid arteries, after they back part of each noftril by a round hole, which is at their upper fore-part. This hole is not formed only by the have entered the fkull. The holes on each fide of the os fphenoides are fix pro- bs fphenoides, which has an aperture near as large as any per, and three common.; —The jirjl is the round one tranfverfe febtion of the finus, but alfo by the palateimmediately below the anterior clinoid proceffes, for the bones which are applied to the fore-part of thefe finufes, pafiage of the optic nerve, and of the branch of the in- and clofe them up, that hole only excepted, which was ternal carotid artery that is fent to the eye.^ The fe- already mentioned. Frequently the two finufes are of cond is the foramen lacerum, or large flit between the unequal dimenfions, and fometimes there is only one tranfverfe fpinous and orbitar procefies : Through it the large cavity, with an opening into one noflril. third, fourth, the firfl: branch of the fifth, and the greater As this bone is extremely ragged and unequal, fo its fliare of the fixth pair of nerves, and an artery from the fubftance is of very different thicknefs, being in fome internal carotid, go into the orbit. Sometimes a fmaJJ places diaphanous; in others it is of a middle thicknefs, branch of the external carotid enters near its end, to be and its middle back-part furpafies the greatefl fhare of diflributed to the dura mater, and a vein, fome call it the cranium in thieknefs. the venous dud?, or Nuck’s aquadudl, returns through it The os fphenoides is joined, by its wings, to the pato the cavernous finus.- The third hole, fituated a rietal bones above, to the os frontis and ofla malarum little below the one jult now defcribed, is called rotun- before, to the temporal bones behind;—by the fore-part dum, from its drape. It allows pafiage to the fecond of its body and fpinous procefies, to the frontal and ethbranch of the fifth pair of nerves, or fuperior maxillary moid bones ;—by its back-part, behind the two finufes, nerve, into the bottom of the orbit. The fourth is to the occipital, where it. looks like a bone with the epithe foramen ovale, about half an inch behind the round phyfes taken off;—to the palate-bones, by the ends hole. Through it the third branch of the fifth pair, or of the pterygoid procefies, and ftill more by the foreinferior maxillary nerve, goes out; and fometimes a vein part of the internal plates of the pterygoid procefles, and from the dura mater pafies out here. Very near the of the finufes;—to the maxillary bones, by the fore-part point of the fpinous procefs is xht fifth hole of this bone : of the external pterygoid plates ;—to the vomer and naIt is fmall and round, for a pafiage to the largeft artery fal plate of the os ethmoides, by the procefius azygos. of the dura mater, which often is accompanied with a All thefe conjundtio'ns, except the laft, which is a fchinvein. -The fxth proper hole cannot be well feen, till dylefis, are faid to be by the future proper to this bone; the cuneiform bone is feparated from all the other bones though it is at firft fight evident, that feveral other fupf the cranium ; for one end of it is hid by a fmall pro- tures, as the tranfveife, ethmoidal, <&c. are confot/nded tuberance of the internal plate of the pterygoid procefs, with it. and by the point of the procefius petrofus of the temporal We fee now how this bone is joined to all the bone. Its canal is extended above the inner plate of the bones of the cranium, and to rhoft of the upper jaw-; pterygoid procefs ; and where it opens into the cavity of 'aind therefore obtained the name of the nuedge-fike the nofe, it is concealed by the thin laminous part of bone. the palate-bone. Through it a confiderable branch of The Face is the irregular pile of bones, compoftng the fecond branch of xhtt fifth pair of nerves is reflecled. the fore and under part of the head, which is divided Often in the middle of the fella Turcica, a fmall into the upper and lower maxillae or jaws. hole or two pierce as far as the cellular fubflance of the The fuperior maxilla is the common defignation given bone; and fometimes at the fides of this fella, one or to the upper immoveable fhare of the face. The fhape more fmall holes penetrate into the fphenoidal finufes. of the fuperior jaw cannot eafily be expreffed ; nor is it The firfl of the common holes is that unequal fifiure neceffary, provided the fhape and fituation of all the at the fide of the fella Turcica, between the extreme bones which compofe it are defcrjbed. It is bounded point of the os petrofum and the fpinous procefs of the above by the tranfverfe future, behind by the fore-part of cuneiform bone. The fecond common hole is the the fphenoid bone, and below by the mouth. large difcontinuation of the external fide of the orbit, left The upper jaw confifts of fix bones on each fide, of between the orbitar procefles of the cuneiform bone, the a thirteenth bone which has no fellow, placed in the midos maxi!tare, vtalx, and palati. In this large hole the dle, and of fixteen teeth. The thirteen bones are, two fat for lubricating the globe, of the eye and temporal offa naf, two effa unguis, two ojja malaruni, two offa mufcle is lodged, and branches pf the fuperior maxillary maxillaria, two ojfa falati, two offa fpongiofa inferiora, nerve, with fmall arteries from the carotid and veins, pafs. and the vomer. The