B I R 



B I R 



entcrtd the lungJ, their ramifications accompany thofecf the 

 pulmonary arteries. They appear alfo to fend branches to 

 the fpine, and the fpaces between the rib?. 



The intercofial arteries do not take their origin from the 

 aorta in numerous and regular branches as in mammalia, but 

 confift; origir.ally of but few vefFels, which are multiplied by 

 anailomofes with each other, and with the arteries which come 

 out of the fpinal canal. An arterial plexus is thus formed 

 round the heads of the ribs, from which a vefTcl is fent to 

 each of the intercoital fpaces. Many of thcfe branches be- 

 fides fupplying the intcrcoftal mufclesand ribs, are continued 

 into the niufcies upon the outfide of the body and the integu- 

 ments. The anallomofis of the intcrcoftal arteries round the 

 ribs is very fimilar to the plexus which is produced by the 

 great fympathetic nerve in the fame fituation. 



The aorta produces no branch which dcferves the name 

 of the phrenic artery, as birds do not poffefs that mufcular 

 feptum of the body, to which the artery of this name is dilbi- 

 buted in other animals. 



The ceel'uic artery is a very large fingle trunk, and arifes 

 from the fore part of the aorta, even higher than the zone 

 of gallric glands. It defccnds obliquely for a fhort way and 

 then gives otF a bninch which foon divides into two or three 

 others that are fpread upon the lower part of the oefophagus, 

 and the fide of the zone of gaftric glands, uniting with the 

 other arteries of the cefophagns above, and extending down- 

 wards upon the po.lerlor fide of the ventricle, andanaHomof- 

 ing with the anterior gaftric artery. The trunk of the 

 cceliac now divides into two very large branches, which from 

 their diftribution we have chofen to call the poftcrior and the 

 anterior gaftric arteries. 



'Y\\t pojltrior gnjlnc artery, almoft as foon as it is formed, 

 detaches x.heJp/en!C artery ; ar.d veiy foon after, it furnifties 

 from the pofterior fide of the vcftel, the ri^hl hepatic artery. 

 This branch p'oceeds to the right lobe of the liver, which it 

 enters on the fide of the hepatic duft ; after having divided 

 into two or three minute arteries on its way to the liver, it 

 fupphes the hepatic duft with a branch which accompanies 

 the duft to the intelline, and is there loft. The pofterior 

 gaftric artery then runs down upon the back of the gizzard, 

 and oppoiite to the origin of the firft inteftine it fends off 

 an artery which proceeds direftlv to one of the caica, upon 

 which and the fide of the next inteftine it is expended, inolcu- 

 lating at the end of the csecum, with branches of the mefcn- 

 tcric artery, which arc diftributed to the adjoining portion 

 of the fmall inteftine. The pofterior gaftric then furniflies a 

 large vefTel which runs upon the g'z'/ard and divides into two 

 chief branches, which penetrate the fubftanceof the digaftric 

 mufcle, in which thty a''e loft. 



The next branch of the pofterior gaftric artciy is the^on- 

 treatic. It runs between the two pancreatic glands, cilpenf- 

 ing branches to each, and to the (luodenum. After this the 

 trunk of the pofterior gaftric divides into two branches which 

 furnifti twigs to the mufcular parietes of the ventricle, and 

 run along the margins of the upper and lower portions of the 

 digaftric mufcle, fupplying them with numerous twigs, and 

 anaftomofing with the ramifications of the other gailric 

 arteries. 



The anterior ga'rJc artei'y defcendsto the angle formed by 

 the bulbus glandulofus and the gizzard, and there fends off 

 a fmall branch which fpreads upon the zone of gaftric glands, 

 and inofculates with the firft ramifications o( the cocliac, and 

 immediately afterwards it detaches a large artei-y, which runs 

 round the fuperior margin of the digaftric mufcle, which it 

 furniftie swith many twigc, and communicates freely with the 

 correfponding branch of the pofterior gaftric artery. 



Three fmall hepatic arteries take their origin frota this 



branch of the anterior gaftric, juil as it paftes over the 

 liighcft part of the margin of the gizzard ; thefe vef- 

 fels enter the fiffure in the left lobe of the liver. The 

 anterior gaftric artery now proceeds along the fore -part 

 of the gizzard, fending one or two branches into the 

 mufcular fubftancc, and near the tendon it terminates in 

 two large veiielf, one of which is diftributed upon the left 

 fide of the digaftric mufcle and the other paffes a httle over 

 the tendon and then divides into two arteries ; which pro- 

 duce feveral branches that difappear in the fubftance of the 

 gizzard, and between the digaftric mnfclcs and the parietes 

 of the ventricle, anaftomofing with the velfels of the pofterior 

 fide. 



The fuperior me/enteric artery takes its origin from the fore 

 part of the aorta a little below the cceliac, and proceeds for 

 iome way without detaching any branches ; after which it 

 experiences the fame kind of divifion and fubdivifion that 

 takes place in mammalia; and the nu.rerous arteries which 

 are thus ultimately produced are fpent upon the fmall in- 

 teftines. One of the firft and largeft branches of the fuperior 

 mefenteric, however, is allotted to fupply one of the caeca, and 

 and eftablifti a communication with the inferior mefenteric, 

 and gaftric arteries. This branch, foon after it leaves the 

 trunk of the fuperior mefenteric, di\ides into two. One 

 defcends upon the rectum, where it meets with the inferior 

 mefenteric artery, with which it produces a very remarkable 

 anaftomofis, fimilar to the mefenteric arch in the human fub- 

 jei3 ; this united artery fupplies the rectum and origin of the 

 cKca. The fecond portion of this branch of the fuperior 

 mefenteric, runs in the fpace between the laft part of the 

 fmall inteftine, and the ccscum of one fide fending numerous 

 branches to each, and at the end of the csecum, communi- 

 cates in a palpable manner with another branch of the fupe- 

 rior mefenteric artery, which runs upon the adjoining part of 

 the fmall inteftine. 



A branch arifes from the anterior part of the aorta, juft; 

 below the lungs ; it is defigned for the nutrition of the 

 organs of generation, and except in the feafon for propa- 

 gation, is fo fmall as to be difcovered with difficulty ; but 

 when the tefticles become enlarged, it is confidei-ably in- 

 creafcd in fize in the male bird, and much more fo in the 

 female, when the ovary and oviduft are developed for pro- 

 ducing eggs. It nearly equals the fuperior melenteric artery 

 during the period of laying, in which ftate we fnaU deicribc 

 it. It is a fingle artery like the cseliac and the mefenteric, 

 proceeds at a right angle from the aorta, and foon fends oiF 

 a branch wh.ich goes into the kidney of the left fide, to 

 which it gives fome twigs, and afterwards emergi:'g from the 

 kidney, it runs in the membrane of the onduA, upon which 

 it is diftributed. After this branch is detached, the artery 

 projeifls a little farther forwards into the cavity and divide* 

 into two branches, one of thefe goes to the ovaiy, in which 

 it ramifies, and furnifties an artery of fome fize to each of 

 the cytts containing the ova. The other is diftributed in 

 numerous branches to the membrane and fuperior parts of the 

 ovidinft, and inofcuiatcs with tlie other arteries of the ovi- 

 duct. It dcferves to be remarked, that this and ail the other 

 arteries which are fnrniftied to the oviduCt, have a tortuoui 

 or undulating courfe, in the fame manneras the v-.;HcIs of the 

 uterus of the human fubjeft. 



There are no regular emulgcnt arteries in birds ; the kid- 

 nies deriving their blood from various fources, which will be 

 pointed out as they occur. 



The inferior extremity is fupplicd with two arteries, which 

 have a feparate origin from the aorta. One corrrefpond* 

 with ihe femoral artery, and the other deferves the name of 

 ifchtadic artery. 



3 G 2 The 



