COMPARATIVE ANATOMY 

 AND PHYSIOLOGY. 



CHAPTER I. 



INTRODUCTORY. 



Comparative anatomy is the science of the 

 structure of animals, considered in their relation to 

 one another; comparative physiology deals with 

 the functions of the parts of which these animals are 

 made up, and, by examining different forms that 

 present various kinds of activities, it throws light on 

 the essential properties of living matter. 



The study of animals is but a part of the wider 

 science of the study of organised matter generally, 

 the science of biology, which takes plants as well as 

 animals for the objects of its investigations. Under 

 the head of biological studies we have, therefore, to 

 group (a) those which regard organisms as working 

 machines, capable of performing various functions ; 

 these studies are physiological, whether animals or 

 plants be separately or simultaneously examined ; 

 (b) in the second place, the parts of which the orga- 

 nism is made up may be investigated, and our studies 

 are then said to be anatomical, if we concern our- 

 selves with isolated types, as does the student of 

 human anatomy ; or they are morphological, when we 

 compare organisms and their parts one with another, 

 and try to draw out the significance of isolated facts, 

 and to leara their bearing on the general scheme of 

 the organisation of living matter. 

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