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the quills to the extremity of the wing', receiving many 

 vei:is of the ioints from the oppofite fide of the fir.gers. 

 Bcfi.lcs thefc large fiiperticial veiiis of the fore arm, there ap- 

 pears to be one, and fomctimcs two, fmall accompany ng 

 veins to the nlnar and interoffcous arteries. 



I'he inferior vcnti cava, before it enters the auricle, re- 

 ceives as ufual the hepatic veins ; thefe are numerous, ard 

 open into the cava, as it pafPes beh.ii.d the liver, or more fre- 

 quently within the fuljilance of that vifcus m the back part. 

 We have recko"ed in the cock two larjje and two fmall hepa- 

 tic veins from the right lobi, and one l;irge branch from the 

 left lobe, brfidts fix minute veins, wiiich came indiliercntly 

 fiom both !)bes. 



The trjnk of the vena cava is very i^ort in the abdnnien ; 

 it feparates into two great branches analogous to \.\\e primary 

 iliac vein!, oppofite to the renal capfuhs ; thefe turn to each 

 Jide, and experience a very fingular dillribution. On coming 

 near the edge of the pelvis each of thefe two veins forms 

 two branches ; one of v/liich coUefls the blood of the lower 

 extremity, as hereafter defcribed ; the other pafTes ilraiglit 

 downwards unbcddtd in the fubllance of the kidney, and 

 admits the fevcral emulgent veins, which are very large, and 

 are feen to pafs for fom.e way obliquely in the kidney, before 

 their termination. The dtfcending branch of the ihiic alfo 

 receives the ovarian vein?, and when arrived at the lower end 

 of the kidney, divides into three branches ; one tranfmits 

 the blood of the n'.ufelcs of the tail and parts adjacent ; ano- 

 ther accompanies the ureter to the fide of the reftum, and is 

 diilributed abo'it the anus and parts of generation, aniwer- 

 ing to the hirnwrrhoidal ■veins ; the third pafTes inwards to 

 the middle line between tlic kidnit s, and there unite- with the 

 correfponding branch of the oppofite fide. The veiTel whic'i 

 is in this manner produced, receives all the blood of the 

 redum from the anus to the origin of the cosca, anallom.of- 

 ing below with the branches of the hxmorrhoidal veins ; 

 and at the upper part of the rcelum, it becomes continuous 

 ■with the trunk of the veins of the fmall intellines, forming 

 the moll remarkable anaftomofis in the body, both on ac- 

 count of its confcqnences and the fize of the veffels by which 

 it is effedttd. By means of this communication, the blood 

 of the vifcera, and the exttmal parts of the body, flows almoll 

 indifferently into the vena cava and vena ports ; for the anaf- 

 tomofing veffels are fnfficiently large to admit the ready paf- 

 fage of a confiderable column of blood in proportion to 

 the whole mafs which circulates in the body of the bird : 

 for in-ilance, in \.\\e goofe, the communicating veins of the 

 pelvis are equal in fize to a goofe quill, and in the ojirich 

 and caffoiuary they are as thick as a finger. The advantage 

 which appears to refult from this remarkable union of veffels, 

 is the prevention of congetlion, or the overloading either the 

 heart or liver with blood, as the one organ has the power of 

 relieving the other. It would feem from this, as well as fe- 

 veral other provifions of the fame kind, that the circulation 

 would be more liable to obllruflion in birds than other 

 animals. It is difficult to fay, however, to what caufe fuch 

 an ttfcA ought to be afcribed. Is it from the compreiTion 

 fuHained by the heart'and other vifcera, by means of the 

 air-cells during refpiration ? Or, is the mode of progref- 

 fion by flight capable of impeding the motion of the 

 blood ? 



The anaftomofis of the pelvic veins, in being the means 

 of conveying common venous blood into the liver, goes to 

 prove, that the blood of the vena portx does not require 

 any peculiar preparation by circuLition in the fpleen or 

 other vifcera, w hich has been conceived as neccffary by fome 

 phyfiulogills to fit it for the fecretion of bile. 



The vena por'.x belongs alaioft exclulively to the right at 



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principal lobe of the liver. It is formed by three branches. 

 The fpknic ■vein is the fmalleft, and is added to the vena 

 porta;, juft as it penetrates the liver on the fide of the hepa- 

 tic dua. The next is made of two branches ; of which one 

 returns the blood of the pofterior gallric artery, and there- 

 fore may be called the pofli-rior grfiric sem ; and the other 

 is fnrnifhed by the pancreas and duodenum, and therefore 

 is the/(7ni-;-<:fl/;c vein. The third and largefl branch of the 

 vena ports is the mefaiteric 'vAn, which not only collefts 

 the blo:d from all the fmall intellines, but likewife re- 

 ceives the inferior mrfcntcric, cr vein of the redum, wh'ch 

 forms the com.munication that has been defcribed with the 

 pelvic veins. 



The iv^ns of the left Ijhe of the liver, are furniflied in the 

 gcofc by thofe which accompany the anterior gaflric arteiy, 

 and fom.e branches from the head of the duodenum. 



The r.nlerior gaflric veins produce two fn^aU trunks, 

 which enter at the two extremities of the fifTure, in the 

 concave furface cf the left lobe of the liver, as it lies upon 

 the edge of the gizzard ; the veins from the head of the 

 duodenum furnilh a fmail veflcl which pafTes backwards to 

 penetrate the poilerior part of the fifTure in tlie left lobe. 



In the cock, the veins that the left lobe of the liver derives 

 from the anterior gaftric, are more numerous than in tha 

 goofe. 



The veins of the zone of gaflric gland'', and of the lower 

 portion of the oefophagus, do not contribute to the fecre- 

 tory veffels of the liver, but proceed to tiie fuperior part 

 of that vifcus, to term.inate in the vena cava ; as does alfo 

 the umbilical vein. 



The vein which returns the blood of the inferior Extre- 

 mitie.:, is divided in the pelvis into two brai'.ches, which 

 correfpond with the femoral and ifchiadic arteries ; the 

 one pafTes throrgh the ifchiadic foramen, and the other 

 through the hole upon the anterior margin- of the pelvis : 

 but the proportion they bear to each other in magnitude, 

 is the very reverie of what occurs in the arteries ; for the 

 anterior vein is the principal one, whilll the other is not a 

 very confiderable vefTel, and receives its fupply of blood 

 from the mufcles at the poilerior part of the joint. 



The femoral vein, immediately without the pelvis, gives 

 branches on both fides, which receive the blood of the ex- 

 tenfor and adduflor mufcles at their fuperior part : the 

 trunk pafTes obliquel-v under the accelfory mufcle of the 

 flexor digicorum, and over the os temoris, Avhere it lies 

 fuperficially ; it then winds under the adduftor mufcles, 

 and gets into the ham, where it receives many mufcular 

 branches, and comes into company with the artery and 

 nerve. It here divides into the //^'a/ and ^rriinfo/ veins. The 

 firft is joined by fome branches from the furface of the 

 joint anfwering to the articular arteries ; it alfo receives 

 the anterior tibial vein which accompanies the artery of the 

 fame name. The tibial vein proceeds down the leg along 

 with the artery on the infide of the deep-feated flexors of 

 the heel : it turns over the fore part of the articulation of 

 the tibia with the metatarlal bone, in order to get upon the 

 inner fide of the metatarfus ; above the origin of the pollex, 

 it receives a ccnimuii'cating branch from the peroneal vein, 

 and immediately after, two branches from the toes : one of 

 them comes from the infide of the internal toe ; the other 

 arifes from the infide of the external and middle toes, unites 

 at the root cf the toes in the fole of the foot, and is joined 

 by a branch from the pollex, before its termination in the 

 internal vein of the metatarfus. 



The peroneal veiu derives its principal branches, along with 

 thofe of the peroneal aitery, from the mufcles on the out- 

 fide of the leg. The trunk of the vein comes out from the 



peroneal 



