10 



THE KINDS OF ANIMAL TISSUES. CELLULAR. 



namely, carbon, hydrogen, and oxygen, are the chemical 

 elements which make tip the vegetable tissues. This is 

 true only as a general statement, and for the higher forms ; 

 the lowest forms of both animals and plants in many 

 cases are composed of the same chemical compounds, cftf- 

 rering only, or mainly, in degree. 



Although there are, apparently, many sorts of tissues in 

 the animal structure, and although various names are given 

 to the different forms under which the tissues appear, they 

 are really only modifications of a few distinct kinds, such 

 as the Cellular or Connective, the Muscular, and the Ner- 

 vous. 



Cellular tissue also better called Connective, Areolar, 

 and Fibrous tissue is composed of filaments variously in- 

 terlaced, and small plates or layers irregularly united, thus 



FIG. 14. 

 FIG. 12. 



.6 



Fat-cells in Cellular or Con- Cellular or Connective or Formation of Cellular 



nectiveor Areolar tissue; a, Areolar tissue, with fat- or Areolar tissue, 



fat-cells ; b, fibers of areolar cells. Human. Magnified from cells. Magni- 



tissue. Highly magnified. 100 diameters. fied I O Q diameters. 



leaving spaces or cavities between them. This tissue is 

 the most abundant of all the materials of the body. It 



