CHAPTEK XV. 



MOVEMENTS GENERAL PROPERTIES OF CONTRACTILE TISSUES. 



Amorphous contractile substance Ciliary movements Movements due to elas- 

 ticity Varieties of elastic tissue Muscular movements Physiological 

 anatomy of the involuntary muscles Mode of contraction of the involun- 

 tary muscular tissue Physiological anatomy of the voluntary muscles 

 Primitive fasciculi Sarcolemma Fibrillse Fibrous and adipose tissue in 

 the voluntary muscles Connective tissue Blood-vessels and lymphatics 

 of the muscular tissue Connection of the muscles with the tendons 

 Chemical composition of the muscles Physiological properties of the mus- 

 cles Elasticity Muscular tonicity Sensibility of the muscles Muscular 

 contractility, or irritability. 



THE organic, or vegetative functions of animals involve 

 certain movements ; and almost all animals possess, in addi- 

 tion, the power of locomotion. "Very many of these move- 

 ments have, of necessity, been considered in connection with 

 the different functions ; as the action of the heart and ves- 

 sels in the circulation ; the uses of the muscles in respira- 

 tion ; the ciliary movement in the air-passages ; the muscular 

 acts in deglutition ; the peristaltic movements ; and the me- 

 chanism of defecation and urination. There remain, how- 

 ever, certain general facts with regard to various kinds of 

 movement and the mode of action of the different varieties 

 of muscular tissue, that will demand more or less extended 

 consideration. As regards the exceedingly varied and com- 

 plex acts concerned in locomotion, it is difficult to fix the 

 limits between anatomy and physiology. A full compre- 

 hension of such movements must be preceded by a complete 



