GENEEAL PHYSIOLOGY 



OP 



MUSCLES AND NEEVES. 



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CHAPTEE I. 



1. Introduction: — Movement and sensation as animal charac- 

 teristics; 2. Movement in plants; 3. Molecular movements; 

 4. Simplicity of the lowest organisms ; 5. Protoplasmic and 

 amoeboid movements ; 6. Elementary organisms, and the gradual 

 ditferentiation of the tissues ; 7. Ciliary movement. 



1. The student who has elected to study the pheno- 

 mena of life probably meets with no more attractive, and 

 at the same time no harder task than that of explaining 

 motion and sensation. It is especially in these pheno- 

 mena that the distinction lies between animate and 

 inanimate objects, between animals and plants. It is 

 true that movements can be detected even in inanimate 

 objects, and, indeed, according to the modern conception, 

 all natural phenomena depend on motion, either on that 

 of entire masses, or on that of the smallest particles 

 of the masses. But the movements of animals are 



