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half. Harwood lias dated ttiefe tnrbinata to be mfmbrwous 

 ill tilt" ca^'iiudry-Ani allatrop ; and Cuvier has obfencd them 

 to be compofcd of bone in the toucan and hornblll. 



The Inferior tiirirui'tim is an ofTcous fold, continued from 

 the pinna of the nails, and united on the other fide to the 

 fe[)tum. See PLte X. in the Jmilomy of Bim's. Fig. J- 

 exhibits the int rior of the nafal cavity of the .fO'^/f, the fep- 

 tum being removed ; a the canal throiigii which the olfac- 

 totv nerve palTes to the nofc ; 1/ the cavity of tlie fuperior 

 turbinatiim ; c its internal tube ; J the external tube ; e the 

 middle turbinatum ; / its deep or firft windinjj ; g the fe- 

 coud ; hi two [)ins pafTed from the windings into the nafal 

 cavity; ( the inferior turbinated bone; /its junction with the 

 feptum ; / the cartilaginous appendix ot' the middle turbina- 

 tum ; III a pin introduced through the external naris ; n the 

 porterior naris. 



T\\c piluilary membrane is fine where it inveflsthe fuperior 

 turbinatum, and thicker and more villous ovef the middle 

 one ; it is covered with pores, whicii difcharge mucus on its 

 furfacc. The blood veffels on the interior of the nofe are 

 beautifully reticulated. 



The bifac-'ji-y ni-rve, as .ilready defcrlbed, arlfes fiom the 

 point of the hemifphere of the cerebrum, and paiies through 

 an ofTeous canal to the fuperior part of the nafal cavity. On 

 arriving theie it breaks into a great number of filaments, 

 feme of wliich are fprcad upon the fuperior turbinatum, and 

 others run about as far on the feptum nafi. See Plate X. in 

 x\\i Ar.ntumv of Birils, fig. i^. ^ the nerve proceeding along 

 the canal above the orbit ; b the appearance of the nerve on 

 the feptum of the duch ; and_/?^. 8. of the f.ime plate exhi- 

 bits a feftion of the head of the heron, a bird with an acute 

 fcnfe of fmell ; a the trunk of the olfadtory nerve ; b its di- 

 ilribution on the fuperior turbinatum, which is very large ; 

 c c the middle turbinatum proportionably reduced in fize ; 

 d inferior turbinatum ; e its conneftion with the feptum ; 

 f the aperture of the external naris. 



Scarpa made a number of experiments with different 

 fpecies of birds, in order to determine their capacity for 

 difcerning odours. He mixed various ilrong fmelling 

 fubftances with their ordinary food, which in fome were 

 taken with indifference, but in others the repugnance to the 

 fcented food was fo great, that the birds perifhed rather 

 than eat it. He was thus enabled to form a fcale of the 

 different degrees of perfcclion in which birds enjoy the fenfe 

 of fmell, which accorded exaAly with the extent of the fur- 

 face allowed for the dillrlbution of the olfaftoi-y nerves. 

 Tiie fcale he has laid is as follows : gallin<t, pjffires, picie, 

 anfcres, accipitres, and grnlU. 



Organ of Tajlc 



The fenfe of tafte is fo imperfect in moft birds, that it 

 might be doubted whttiur it cxifted at all or not. The form 

 and motions of the tongue unfit it for being applied to the 

 fuperlicies of fubftances ; the glairy tenacious fluid, with 

 which the furfaces of their mouths are bcfmeared, is not cal- 

 culated for the folution of fapid bodies ; and the ftiape and 

 flrufturc of the paplllx of the tongue fcem to render them 

 neariy incapable of imprelFion ; and further it may be ob- 

 ferved, that birds commonly fwallow their food without ex- 

 amination, or a minute divilion of its parts. 



The motions and internal formation of the tongue have 

 been already difcuffed ; it only remains, therefore, to no- 

 tice the figure and integuments ; but as thefe have been 

 defcribed by natural hiftorians in almoft every genus, it is only 

 iicoefTary to fpeak of them in a very general way at prcfent. 



The /unn of the tongue may be commonly gueffed at from 

 the Ihape of the bill, with which it correfponds in a certain 

 degree. In tl\e gallina znA pajera it is an elongated trian- 



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gle, the point being turned forwards ; in tlie graU<i it is ge- 

 nerally of the fame figure, the triangle being however 

 lengthened in proportion to the bill ; the broad-billed birds, 

 as the/wJn, goofe, ^c. have the tongue broad and round at 

 the end. 



The parrot has a thick round flefliy tongue, not unlike 

 that of mammalia. 



Several birds have the tongue bifid at the point. 

 The African ojlrich has a broad tongue, but fo fliort, that 

 its exiilence has been often doubted. The New Holland 

 ojlrich has a very thin fmall tongue, and neariy an equilate- 

 ral triangle. 



The papillc, or projefting points of the integument of 

 the tongue are very various in their fliape and arrangement. 

 In moft inftances the tongue is fmooth, except at its bafe, 

 where it is furniflied with (harp reflex papilla:, which are 

 commonly cartilaginous, and often covered with bone. In 

 many birds there are proceffes along the upper furface or the 

 edge of the tongue, which are inverted with a horny or of- 

 fcous fubftance. The vulture has cartilaginous ferrae along 

 the edges of the tongue. The toucans have fine horny 

 briftles along tlie fides, which give their tongue a rtfem. 

 blance to a feather. 



On the lateral parts of the back of the tongue of the 

 Jlamiiigo, there are two rows of bony proceffes, ihaped like 

 hooks, with their points turned backwards. 



The duch, goofe, fivan, (sfc. have, befides fharp briftles 

 and dcnticulations, fome rows of little ofTcous plates with 

 their thin edges turned toward the fauces, 



Eirds have frequently liie edges of the pofterior nares, 

 and other prominent parts of the fauces furniftied with re- 

 flefted fpiculae, fimilar to thofe on the tongue ; from 

 which it is probable, that both are intended to affift in the 

 aftion of fwallowing the food, rather than to receive the 

 impreftlons of fapid fubftances. 



The parrot is the only bird which appears to tafte its food, 

 and hence it pofleffes foft papilla;, of which fome are really 

 fungiform. 



It is probable, that the humming birds pofTefs the fenfa- 

 tion of tafte, as their tongue is flexible and tubulated, 

 through which they fuck, lik; infects, their fluid aliment. 

 Organ of Hearing. 

 Birds are unprovided with the concha, or that external 

 projeftion of the ear which is obferved in man and quadru- 

 peds, for collefling the rays of found ; but to compenfate 

 for the want of it, fome of the internal parts of the organ 

 are formed upon a larger fcale. The feathers are arranged 

 in fome fpecies, however, around tha meatus auditorius in 

 fuch a way as to produce, in a degree, the effeft of the con- 

 cha. This is moft obfervable in the o'wls, in which alfo the 

 membrana tympani lies at the bottom of a cavity, which is 

 luied by a refleftion of the common integuments that forms 

 folds fomething analogous to the projectioas of the human 

 concha ; and in the ti'hite oivl, there is a fquare membrane, 

 which ferves as an operculum to the anterior part of the ca- 

 vity. 



The frame of the membrana tympani, or the bone which 

 furrounds it, is more prominent in fome birds than in others; 

 but generally it does not projeit fufhciently to deferve the 

 name of a canal. Ir is imperfeft anteriorly, where the arti- 

 cular bone is fituated, to which the membrana tympani is in 

 part attached. In the ichite owl, however, the olFeous 

 frame of the meatus is completed by the bones of the 

 head alone. 



The membrana tympani is always more or lefs of an 

 oval figure. It poffefles the fame llruilure as in mam- 

 malia, but is very thin ; the convex, or conic furface, is 

 7 external, 



