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EXHALENT SYSTEM. 



Q. In what respects do exhalation and secretion agree? 



Jl. In this, that both operations separate fluids differ- 

 ent from the blood. 



Q. In what respects do exhalation and secretion differ? 



*#. Chiefly in these particulars; that in the secreting 

 organs there is an intermediate organ between the arteries 

 and excretories, but there is none between the arterial 

 terminations and the exhalents; that the secreted fluids 

 are much more complicated than those which are exhaled; 

 that exhalation takes place from an infinite number of dis- 

 tinct vessels, while the secreted fluids are directed to one 

 or two tubes which convey them from the organ; that the 

 secreted fluids are thrown off, becoming excrementitious, 

 while the exhaled are most of them recrementitious ; that 

 numerous surfaces receive the exhaled matters, while the 

 secreted are principally poured out on the mucous and 

 cutaneous. 



Q. Name some of the exhaled fluids. 



/?. There is the fat, and the serum, the synovia, the 

 marrow. 



Q. Now indicate some of the secretions. 



*#. You have the bile, urine, semen, pancreatic fluid, 

 saliva, and others. 



Q. What do you mean by exhalents? 



*ft. They are small tubes or vessels arising from the 

 capillary system, continuous with the arteries which bring 

 them the materials for exhalation. 



