LESSONS FROM THE MICROSCOPE. 103 



voluntary We ^ ave seen that voluntary muscles 

 muscles (14). are made up of bundles of fibers. This 

 is beautifully shown here. We also see the cross- 

 markings, or strice, which is a peculiarity of volun- 

 tary muscles. An examination of a piece of cooked 

 beef will be helpful in connection with this view. 



The all-important gastric juice, so much 

 needed in a proper digestion of the 

 food, is secreted by glands of the 

 stomach wall. Such a gland is here represented in 

 a very admirable manner. From the little mouths 

 here seen, exudes the gastric fluid during the pro- 

 cess of digestion. 



At (16) and (17) are representations of 



Xerve -fibers v ' 



of Brain (16), nerve-fibers of the brain. Their healthy 

 action, the abundance of their cells and 



their proper nourishment largely determine our 



mental capabilities. 



The hepatic or liver vein, by which 

 lie- *^ e blood is collected and carried from 



paticvein(i8).the liver toward the heart, is here 



shown as passing through the adjacent liver sub- 



stance. The meshes of the liver capillaries are also 



seen. In these the bile is secreted. 



The microscopic appearance of the 



Kidney , , * A i i i - i 



structure (it>). structure or the kidneys is here repre- 

 sented (19). The peculiar little cap- 

 sules or balls, called Malpighian Corpuscles, are a 

 part of the mysterious organism provided for the 

 secretion of the urea from the blood. 



