LYMPHATIC SYSTEM. Gil 



all parts of the body, appear still to be confided to the 

 ordinary sanguiferous vessels. In the complex systems 

 of the vertebrata, however, a distinct chyliferous appa- 

 ratus is appropriated to the absorption of the nutritious 

 part of the food, and to its conversion into chyle or almost 

 into blood, and in the same elevated tribes of animals a dis- 

 tinct vascular system, the lymphatic or absorbent, is allotted 

 to receive the decayed materials from every point of the 

 body, and to convey them to the blood, to be discharged 

 with the excretions. 



The lymphatics appear to be porous or absorbent at all 

 points of their surface, as the tubuli of glands are secern- 

 ing throughout their course, and probably both these sets 

 of permeable tubes are equally closed at their commence- 

 ments. By the introduction of these absorbents into all 

 the tissues of the body, they are enabled to grow by in- 

 tus-susception, and to retain all their proportions while they 

 increase in bulk. From their function they have been termed 

 absorbents, and lymphatics from the limpid fluid they convey. 

 Though differing in function from the lacteals, as the lacteals 

 from the veins, or the liver from the kidney, they have nearly 

 the same relation to the venous or sanguiferous system, and 

 enter it at the same place, through the medium of the 

 thoracic ducts, which are canals common to the chyliferous 

 and lymphatic apparatus. While the lacteals convey only 

 chyle to the blood, and originate solely from the alimentary 

 tube, the lymphatic absorbents convey the dissolved tissues 

 of every living organ, and originate from or traverse every 

 point of the body ; and although these two systems first 

 appear simultaneously in the class of fishes, the plexiform 

 convolutions of their vessels, forming their so-named ganglia 

 or conglobate glands, appear earlier in the lymphatic than 

 the chyliferous system. The limpid contents of these vessels 

 are sometimes yellowish, reddish from the presence of blood 

 globules, or whitish in colour, they contain albumen and 

 fibrin and easily coagulate, and they convey globules, like 

 chyle, blood, or milk. 



The lymphatics abound in the tissues of all the verte- 

 brated classes, following the course chiefly of the larger 

 and deep-seated arteries and veins, and occurring over all 

 the subcutaneous parts, so that they appear to confer the 



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