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 163 Part L A N A T O M T. might alfo deferve the name of turbinata, but are uncerfpongio/um' inferius rcfts. Along the outfide of this tain in their bulk, fituation, and number. plate, the perpendicular foffa made by the palate-nerve They are joined to the ofla maxillaria, palati, and un•is obfervable. efpedally in old fubjeds. At the upper part of this nafal plate, the palate-bone guis,Their ufe is, to ftraiten the nofti ils, to afford a large divides into two procefles, which were already named or- furface for extending the organ of fmelling, to cover bilar;—between which and the body of the fphenoid part of the and to aflift in forming the bone, that hole is formed, which was mentioned as the under part ofantrathemaxillaria, lacrymal duds, the orifices of which laft of the holes common to the fphenoid bone. Some- into the nofe are concealed by thefe bones. times this hole is wholly formed in the os palati, by a Vomer, or bone refembling a ploughftiare, is the crofs plate going from the one orbitar procefs to the o- thirteenth of the upper jaw, without a fellow, forming ther. A nerve, artery, and vein belonging to the no- the lower and back-parts of the partition of the nofe. ftrils, pafs here.—The anterior of the two orbitar profigure of this bone is an irregular rhomboid.—■ cefles is the large!!, and has its fore-part contiguous to ItsThe flat and fmooth.—•—Its pofterior edge apthe back-part of the maxillary finus, and its upper fur- pearsfidesin anareoblique at the back-part of the noface appears in the bottom of the orbit, behind the back- firils. The upperdiredion one is firmly united to the bafe of part of the os maxillare and planum,.—It has cells be- the fphenoid bone, and the nafal plate of the ethhind, refembling thole of the ethmoid bone, to which it moid ; and, when it can beto got feparated, is hollow, for is contiguous; it is placed on the aperture of the finus fphenoidalis, fo as to leave only a round hole at its upper receiving the proceflus azygos of the fphenoid. The fore-part*—The other part of the orbitar procefs is ex- anterior edge has a long furrow in it, where the middle tended along' the internal fide of the upper back-part of cartilage of the nofe enters.^ The lower edge is firmthe maxillary tuberofity, to the bafe of the fphenoid bone, ly united to the nafal fpines of the maxillary and palatebetween the root of the proceflus azygos and the ptery- bones.- Thefe edges of this bone are much thicker than its middle, which is as thin as the fine!! paper. goid procefs. The palate-bones are joined to the maxillary, by Its fituation is not always perpendicular, but often inthe fore-edge of the palate fquare-bone, by the tranf- clined and bended to one fide, as well as the nafal plate verfe palate-future ~By their thin nafal plates, and part of the ethmoid-bone. of their orbitar procefies, to the fame bones, by the pa- The vomer is convex at its upper part, and then is lato-maxiliares futures :—By their pterygoid precedes, ftreight as it is extended downwards and forwards, where and back-part of the nafal plates, to the alae vefpertilio- it is compofed of two plates; the edges of which have a num, by the fphenoid future :—By the tranfverfe ridges great number of fmall proceites, difpofed fomewhat like of the nafal plates, to the ofia fpongiofa inferiora, by the teeth of a law, but more irregularly, and feveral of .contad:; hence frequently there is an intimate union of them are refledted back. Between thefe plates, a deep the fubftance of thefe bones in old llculls : By the fofta is left, which, fo far as the top of the curv.ature, erbitar procefles, to the ofla plana and cellulse ethmoi- is wide, and has ftrong fides, for receiving the proceflus deae, by the ethmoid future: To the body of the azygos of the fphenoid-bone. Beyond the arch for■fphenoid bone, by the fphenoid future:——By the inter- wards, the fofia is narrower and (hallower gradually to nal edge of the fquare-bones, to each other, by the lon- the point of the bone, receiving for fome way the nafal gitudinal palate-future ; and by their nafal fpines, to the lamella ethmoidea, which is fo cloftly united to the vovomer, by the fpinous future. mer, by the little proedfes piercing into its fubftance, as The palate-bones form part of the palate, nofirils, or- to prevent any feparation. The middle cartilage of the bits, and foflae, pterygoidea:, and they cover part of the nofe fills up what remains of the fofla at its fore-part. finus maxillares, fphenoidales, and ethmoidei. The pofterior edge of the vomer, which appears aOssa Turbinata, or fpongiofa inferiora, refemble bove the back-part of the palate-bones, is broader above; the fuperior ofla fpongiofa in Ihape and fubflante, but but as it defeends forwards, becomes thinner, though it have their anterior and upper edges contiguous to the is ftill folid and firm. The lower edge of this bone, tranfverfe ridges of the nafai procefles of the maxillary which refts on the nafal fpine of the palate and maxiland palate-bones. From their upper ftreight edge, lary bones, has a little furrow on each fide, of a fmall two fmall procefles ftand out: the pefterior, which is the middle ridge, anfwering to the fpines of the bones of broadeft, defeends to cover feme of the antrum Highmo- different fides, and the interftice between them. This rianum; the anterior rifes up to join the os unguis, and edge and the upper one meet in the pointed fore-end of to make part of the lacrymal dud. this bone. Below the fpongy bones already mentioned, there are The body of the vomer has a fmooth furface, and fi> fbmetimes two others, one in each noftril, which feem lid, but thin fubftance ; and towards its fides, where it to be a produdion of the fldes of the maxillary finus is thickeft, fome canctlli may be obferved, when the turned downwards. When this third fort of fpongy bone is broken. bones is found, the middle one of the three in each no- It is joined above to the fphenoid and ethmoid bones, firil is the large!!, and the lowefi is the fmalle!!. Be- and to the middle cartilage of the nofe, by fchindylefis; fidcs all thefe, there are often feveral other fmall bones to the maxillary and palate-bones, by the fpiflaoding out into the noitrils, that, from their fnape, —below, ncus future. The