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foU of the wing. The nerve now turns round the neck of 

 the radius, beneath the nnifcles, and forms two branches; of 

 which one partes under the mufcles to the outer fide of the 

 uhia, along which it runs fuperfieially to tlie hand ; the 

 other branch pafles on the radial fide, but more deeply 

 amongll the miifc'es, goes under the annular ligament of the 

 carpus, proceeds between the branches of the metacarpus, 

 and is finally loll on the back of th<. ligiti. 



Although Cuvier has given a more accurate defcription of 

 the ncr\e3 of the lower extremity, than of thofe of the wuig, 

 it nevcrthelrfs needs correftion in fcveral particulars, which 

 we have fupplied. 



The oblnrator and femoral nerves arife from the fame 

 plexus which is formed by the two lall lumbar nerves, 

 by a communicating branch from the firlt facral pair. 

 The obturator nerve pafics through the upper part of the 

 foramen ovale, and is dillributcd to the mufcles around the 

 hip joint, efpccially the addudlor. The femoral nerve pafTes 

 out of the pelvis in company with the artery, over the upper 

 edge of the ilium. It divides into three branches, which 

 are difperied amongll the mufcles and integuments on the 

 anterior and inner part of the thigh. Some of thefe fila- 

 ments arc long, and defccnd fuperfieially for a confiderable 

 way upon the limb. 



The ifchiailtc nerve is compofed of the five fiiperior facral 

 nerves ; and as foon as it departs from the plexus, even with- 

 in the pelvis, is eafily feparable into its primary branches. 

 Immediately after it pafTes through the ifchiadic foramen, it 

 fends filaments to the mufcles on the outer part of the thigh ; 

 it then proceeds under the biceps nnifcle, ah)ng the back of 

 the thigh, about the middle of which it becomes divided into 

 the tibial and the peroneal nerves. 



The tibial nerve, even before it arrives in the ham, fe- 

 paratcs ii to fevcral branches, which pafs on each fide of the 

 blood-velTcls, and are chiefly diltributed to the mufcles on 

 the back of the leg. Two of tlicfe branche"-, however, are 

 differently difpofed of : the one accompanies the poftcrior ti- 

 bial artery down the leg, paffes over the internal part of the 

 pulley, and is loft in fmiU filaments, and anaftomofes with a 

 branch of the peroneal nerve, on the inner fide of the mcta- 

 tarfus ; the other branch runs down on the peroneal fide of 

 the leg, along the deep featid flexors of the toe?, paffes in 

 a (heath forn:ed for it on the outer edge of the moveable 

 pulley of the heel, and proceeds under the flexor tendons 

 along the metatarfal bone, to be dillributed to the internal 

 part of the two external toes. 



The peroneal nerve is dirccled to the outer part of the 

 leg ; it dips in above the gaftrocnemii mufcles, and runs 

 through the fame ligamentous pulley that tranfniits the ten- 

 ded of the biceps mufcle ; it then detaches fome large fila- 

 ments to the mufcles on the anterior part of the leg, under 

 which it divides into two branches, which proceed clofe to- 

 gether, in company with the anterior tibial artery, to the 

 fore part of the ankle joint, at which place they feparate ; 

 one pafTts fuperfieially over the outer part of the joint ; 

 the other goes firll under the tianfverfe ligament which 

 binds down the tendon of the tibialis anticus mnfcle on tli'* 

 tibia, and then over the inner part of the joint, below which 

 it divides into two branches, the one is dillributed to the in- 

 ner fide of the mctatarfiis and the tibial fide of the pollex 

 and to the next toe ; the other turns towards the centre of the 

 metatarfal bone, and penetrates the tendon of the tibialis anti- 

 cus juft at its iufertion, and then rejoins the branch of the per- 

 oneal nerve itaccompanieddown the leg. They continue their 

 couife together agaiu in the anterior furrow of the meta- 

 tarfal bone ; and at the root of the toes, feparate once 

 more, and proceed to the jntcrfpaces of the tkrce anterior 



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toes, and each divides into two filaments, which run along 

 the fides of the toes to the nail. 



Organs of Touch. 



As the fenfe of touch is bellowed upon animals to enable 

 them to difcern the forms and Hates of aggregation of exter- 

 nal matter, it refidcs more cfpecially in the extreme parts of 

 their bodies, and when moll pcrfef!i, exills in fome member 

 which is cohftrufted for including or taking hold of extra- 

 neous fubllances. There is no part of the body of birds ca- 

 pable of conveying an accurate impreffinn of touch, but 

 the feet and the bills ; their upper extremities and tail being 

 fimply inllrumenls of motion. DiH'erent Ipecits enjoy this 

 in difl'eient degrees, and poffefs it more or lefs in the bill or 

 feet, in proportion as they employ thefe parts in the purfuit 

 or examination of their food ; thefe being the only occafions 

 on which birds exercife their funftions ot touch. TUe/ean- 

 fores, acdpitrcs, anA pajfcrine tribe have moll fenfiition in their 

 feet, while the gralU and anjlres, efpecially thofe that have 

 long or broad bills for feeling out their food, like the/nips, 

 or dui:i, polfcfs a very great fufceptibility of imprefEon in 

 their bills. 



The organization of the feet of birds, as far as concerns 

 their offices as inllruments of touch, is fimilar to that of 

 the digitated mammalia and reptiles. The fi<in on their 

 lower furfaces ij endowed with more than common vafcnla- 

 rity, is largely fupphed with nerves, and is elevated into 

 thofe little regular eminences called papilla, in which the 

 fenfe of touch more immediately refides. 



The ilrnfture, on which the fenfibility of the bill depends, 

 is diflerent from the preceding. It confills in the magni- 

 tude and dillribution of the filth pair of nerves. Thefe are 

 divided, as in mammalia, into three biancheF, the cphthal- 

 niicy the Jiiperior maxillary, and the inferior maxillary. 



The ophthalmic enters the orbit by a hole befide the optic 

 foramen, paffes for fome way in an offeous canal before 

 it arrives in the nafal cavity, where it dillributes fome 

 branches to the fcptum and turbinata, and to the external 

 naris, and then goes on as two branches ; one runs in the 

 fubllance of the upper jnw, whicli it perforates at the end 

 in many filaments, to terminate under the horny integument 

 of the bill; tlie other paffes between the meml-rnne of the 

 palate and the bill, and is loll in a number of hbiils at the 

 apex of the bill. 



The_/u/ieWor and inferior maxillary nerves come out of the 

 cranium by the fame hole. The fuperior, after difpenfing 

 branches to the mufcles in its courfe, is finally dillributed 

 to the lateral parts of the bill, which, if notched along the 

 edge, as in fome water birds, each denticnlation receives fe- 

 vcral filaments. The inferior maxillary delcends to the lower 

 jaw, which it penetrates, after fending a branch to the inte- 

 guments of the fide of the bill ; and running in the maxillary 

 canal, fends filaments to the edge of the bill, and terminates, 

 like the ophthalmic, on the apex of the lower mandible. 



Thefe nerves are of great fize in the goofe, cluck, Isfc. in 

 which they render the bill a very delicate organ of touch. 

 See Plate X. in the .Anatomy of Birds. Fig. 4. is the fec- 

 tion of the head of a duck, made by dividing the organ of 

 fmell longitudinally, and by removing the bill and bone of 

 the mandible, in order to bring into view the d'llribution of 

 the fifth pair of nerves : a a the ophthalmic nerve coming 

 from the upper part of the orbit, and proceediu./ along 

 the feptum nafi ; b thr branch which paffes in the fubllance 

 of the mandible, r.> ^t loll on the point of the bill, c the 

 branch that nins 01. the membrane of the palate to the end 

 of the bill ; (^/ the luperior maxillary nerve dividing on the 

 membrane of the pjhte, and lending its filaments to the 

 denliculi on the Ude of the bill j e the inferior maxillary run- 

 ning 



