ANGIOLOGY 257 



the pancreas and the duodenum, and terminate around the celiac 

 axis with the lymphatics of the liver, the proventriculus, the giz- 

 zard, and the spleen, forming a rather voluminous plexus (Lauth). 



The aortic plexus represents the receptaculum chyli and gives 

 origin tp two thoracic ducts, mentioned above, which passing on 

 each side of the bodies of the vertebrae, pass one right and one left, 

 over the Imigs, from which they receive lymph vessels, and terminate 

 after receiving the lymph vessels of the wing, into the jugular vein 

 of their respective sides. The left thoracic duct, before emptying 

 into the vein, receives the trunk of the lymphatics of the left side of 

 the neck, and the right duct that of the right side of the neck, each 

 tributary collecting lymph from all the structures of its side. 



The l)7inphatics of the wing foUow the course of the brachial 

 artery, forming a plexus around it. These vessels are well developed 

 in the elbow region. The principal trunk, following the humerus, 

 receives collateral branches in its upper third. This vessel, when 

 nearing the chest, receives two or three large lymph vessels from 

 the pectoral muscles, and a branch which accompanies the brachial 

 plexus. 



The lymph vessels of the head accompany the branches of the 

 jugular vein, collecting the lymph from the structmres of the head 

 and the neck. 



The lymphatic vessels commxmicate at the anterior and posterior 

 oblique anastomosing vessels. At the lower part of the neck each 

 trunk receives a vessel, which accompanies the carotid arteries. 

 Further on they are provided with a lymph gland which rests on the 

 jugular vein. 



THE Blood and Its Functions 



The special function of the blood is to nourish all the tissues of the 

 body, and in this way to aid growth and repair. It furnishes mate- 

 rial for the purpose of the elaboration of body secretions; it suppUes 

 the organism with oxygen; and it carries away carbon dioxid and 

 other effete material. Blood is constantly in circulation. 



Blood is red, opaque, and is, in the fowl, quite viscid. The 

 exact tint of the blood depends on whether it is drawn from an artery 

 or from a vein. Blood from a vein has a purphsh tinge while that 

 from an artery is a bright scarlet. The color of blood is largely due 

 to pigment in the erythrocyte, called hemoglobin. 



The reaction of the blood is alkaUne, due to the phosphate and the 



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