GENERAL MORPHOLOGY AND PHYSIOLOGY 



General Zoology : Animal Morphology. — In the vital phenom- 

 ena of animals a certain degree of similarity can be followed 

 through the entire animal kingdom; the way in which animals are 

 nourished and repiroduce their kind, how they move, and how they 

 gain experience, is essentially the same in great groups, and even 

 widely separated forms show many agreements. Corresponding 

 to this, the apparatus which is concerned with the above-men- 

 tioned functions, the organs of nutrition and reproduction, of 

 motion and sensation in their grosser and finer structure, and in 

 their ontogeny, must be similar to one another and show evidence 

 of some fundamental characters which always or frequently recur. 

 All this needs a general explanation before we can go into a 

 description of the separate branches of animals. This explanation 

 is the subject of general zoology, specially of general anatomy and 

 embryology, or animal morphology. 



(Ecology or Biology. — If by means of anatomy and embryology 

 we have learned the general character of the animal organism, we 

 must yet farther study its relations to the environment. For this 

 study of the conditions of animal life, oecolog}' or biology, we have 

 to consider the geographical range of animals, their distribution 

 over the surface of the earth and in the difEerent depths of the 

 sea; further, the reciprocal relations of animals and plants, and 

 of beast to beast, as these find special expression in colony-build- 

 ing, symbiosis, parasitism, etc. 



General Anatomy. — In the case of TJeneral Anatomy, with 

 which we shall begin, the fundamental proposition will be, IIow is 

 an organism formed from its const itiieut parts? We shall thus in 

 spirit follow the opposite course from that which anatomy actually 

 takes, for this resolves the animal body into its elementary parts, 

 its organs, tissues, and cells. Instead of analytical we will pursue 

 synthetic anatomy. 



The svirthesis of an organism, of which by general anatomy we 

 can only gain an idea, actually takes place in nature during the 



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