LESSONS FROM THE MICROSCOPE. 101 



of capiiia- At (3) we have represented the net- 

 ries between WO rk of capillaries which constitutes 



Arteries 



and veins (3). the connection between the arteries and 

 veins. Here the outer and middle walls of the 

 arteries have disappeared, and only the inner coat 

 remains. The filtering process can thus take place 

 with little difficulty. 



of MUCOUS All cavities of the body which com- 

 Membrane (4.) municate directly or indirectly with 

 the outside surface are lined with a soft, smooth 

 membrane called the mucous membrane. This is a 

 continuation of the skin. At the lips, for example, 

 we may see that the skin merges into a softer and 

 more sensitive coat, the mucous membrane. Here, 

 at (4) you may notice its net- work of capillaries. 

 1.00 eda>ii- At (5) we see the capillary meshes of 

 lariesoftne the skin. Through their folds are 



absorbed many substances which are 

 then carried into the system, as we learned under 

 Absorption. The activity of these capillaries as 

 absorbents makes it possible for sailors to quench 

 thirst by spraying their garments with sea water 

 when their supply of fresh water is exhausted. The 

 wet garments come in contact with the skin, and the 

 moisture is absorbed. 



This (6) gives the eye an opportunity 



tinai vim**) to ai d tne m i n <l in comprehending the 

 outer structure of the villi. The vein 

 capillaries which take up the digested food are here 

 shown. 



