CHAPTER SIXTH. 



ICHOROLOGY, OR HISTORY OF THE ORGANS OF SECRETION.— 

 THE LYMPHATIC AND SECRETORY SYSTEM. 



DEFINITIONS AND DESCRIPTIONS. 



498. The Body is Constantly Undergoing a Change.— 



We have seen that the human body is constantly undergoing 

 Fig. 274. changes in its constituent 



parts. The nutrient por- 

 tion of the food designed 

 for the support and growth 

 of the different tissues is 

 conveyed by the lacteals to 

 the left sub-clavian vein, 

 mi$ w ^ ere ft ent ers the general 

 circulation ; while the par- 

 ticles which are constantly 

 set free in all parts of the 

 body are, by vessels of the 

 same general character, 

 called lymphatics, con- 

 | * veyed to the blood and 

 x thence to the lungs. 



499. The Lacteals a 

 Variety of the Lymphat- 

 ics. — A more correct 



A, «, Deep-seated Lymphatic Gland, a, &, Lym- , 



phatics which supply and Empty the Ghmd. b arrangement, nowever, 



a, Superficial Lymphatic, less complex in struc- Apings both Sets of absOl'b- 

 ture. c, n, Lymphatic laid open to show the © 



Valves, c, d, e. ent vessels under the class 



of lymphatics, making the lacteals only a variety, since their 



49S. How is it that the body is constantly undergoing change? 499. What may thtf 

 lacteals be properly called ? 



