ELEMENTARY STRUCTURE OF ORGANIZED BODIES. J5 



cells, the intercellular spaces being filled with a more com- 

 pact substance called the hyaline matter. Figure 4 repre- 

 sents a slip of cartilage from a horse, under 

 a magnifying power of one hundred and twen- 

 ty diameters. 



43. The osseous or l>ony tissue differs from 

 the cartilaginous tissue, in having the meshes 

 filled with salts of lime, instead of hyaline sub- 



Fig. 4. 



stance, whence its compact and solid appearance. It con- 

 tains, besides, minute, rounded, or star-like 

 points, improperly called bone-corpuscles, 

 which are found to be cavities or canals, and 

 ^iBO'iis -^r are some ti mes fancifully branched, as is seen 

 ^^^^M^^U m fig ure 5? representing the section of a horse 

 bone, magnified four hundred and fifty times. 



44. The muscular tissue, which forms the flesh of ani- 

 mals, is composed of bundles of parallel fibres, which, in the 

 muscles under the control of the will, are commonly crossed 

 by very fine lines or wrinkles, and possess the peculiar 

 property of contracting or shortening themselves, under the 

 influence of the nerves. Every one is sufficiently familiar 

 with this tissue, in the form of lean meat. 



45. The nervous tissue is of different kinds. In the 



nerves proper, it is composed of 

 very delicate fibres, which return 

 back at their extremities, and form 

 loops, as shown in figure 7, repre- 

 senting nervous threads, as they pig. 7. 

 terminate in the skin of a frog. The same fibrous 

 structure is found in the white portion of the brain. 

 But the gray substance is composed of very minute granu- 

 lations, with larger cells, collected in clusters, as seen in 

 figure 8. 



46. The tissues above enumerated differ from each other 





7 



