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CHARACTERISTICS OF ARTERIES. 



Branches of arteries leave the main trunk, at obtuse, acute, 

 and right angles. 



The united capacity of all the small branches is much greater 

 than the parent trunk. 



Arteries do not taper, but diminish in size, by giving off 

 other trunks and branches. 



The blood in arteries goes slower the further it is from the 

 heart. 



Arteries are placed in the aspect of flexion in limbs, rather 

 than of extension. 



As compared with veins, they are deep-seated on the inner 

 surface of the feet and legs. 



The coats of the arteries are thick, except in the brain, spi- 

 nal cord, and the interior of bones. 



They are enclosed in a loose cellular sheath to allow of ver- 

 micular motion and dilatation. 



They terminate in capillaries. 



THE MICROSCOPIC ANATOMY OF AN ARTERY 



Reveals the existence of three coats. 



i. An external coat made up of areolar tissue, and yellow- 

 elastic fibres; the fibres being disposed longitudinally. 



2. A middle coat, consisting of muscular and elastic fibres, 

 both arranged in a circular form, so as to form a tube. 



3. An internal coat composed of a basement membrane of 

 elastic material, and an epithelial membrane lining the base- 

 ment membrane. 



The coats are all united together by areolar tissue. 



Arteries have no valves, excepting one at the entrance to the 

 aorta and pulmonary artery. 



An artery is distinguished by its cylindrical form ; and bleed- 

 ing from an artery is known by its pulsatory character. 



An artery may be recognized by its dirty yellowish-white 

 color. 



