DIFFERENTIATION OF THE ANIMAL BODY. Iiy 



fibrous connective tissue, which pervades the body of higher animals 

 and binds together the muscles, the nerves, and other tissues; 

 cartilaginous tissues, Fig. 23; tendons and ligaments; bone, Fig. 24; 

 dentine, and enamel; and the nutritive fluids, as blood and lymph. 



128. Practical Exercise for the Library (and Laboratory). Demon- 

 strations may be made of the chief types of tissue under the micro- 

 scope, and the students allowed to examine them rapidly. Study 



B 



FIG. 23. Cartilage. A, hyaline cartilage; B, fibrous cartilage. In the latter a 

 large part of the intercellular substance is conspicuously fibrous. The cells occur 

 in pockets (p) in the matrix; /, intercellular fibres. 



Questions on the Figure. What are the points of similarity and 

 of difference in these two types of cartilage? In what way do the 

 multicellular pockets arise? How do the unicellular pockets arise? 

 What are the nature and origin of the intercellular substance in each 

 case? 



the various figures in this and other texts, and identify the cells 

 and the intercellular substance. What of the amount and charac- 

 ter of each? What are the exact functions of the various types 

 mentioned in the preceding section? 



129. Muscula" tissue is one of the most distinctive tissues of 

 animals. Its prime function is contraction. The simplest pro- 

 toplasm is contractile in some degree, but muscle cells are peculiarly 

 so. Furthermore, because of their elongated form their contraction 

 takes place in one direction only, and hence a muscle contracts 

 much more effectively than a simple cell. There is little intercellular 



