10 THE CAT. [CHAP. I. 



arc very far from enabling us really to understand the absolutely 

 ultimate composition of tbc body, 



Anothci- science which concerns the structure of the body is 

 Coniparaiivc Anatomy. By it the structure of the whole body or of 

 any part of the body is compared with the bodies or corresponding 

 parts of the bodies of other creatures. The comparative anatomy 

 of animals is sometimes called Zootomy. The above inquiries all 

 refer to the number, shape, arrangement, connexion and relative 

 position of parts (whether large or minute), and to the resemblances 

 and differences between different living creatures thus regarded. 



The inquiries which constitute the next set of Biological sciences, 

 refer to the actions which the cat's body performs. 



Obviously the animal moves, takes food, and, if young, increases 

 in size. The slightest observation convinces us that it has senses, 

 feelings, and emotions, more or less similar to our own. If emaciated 

 by starvation we see that it can by food regain its former bulk, and 

 we may observe that triHing wounds or injuries may be repaired. 

 Others of its actions normally result in the production of a new 

 individual — another generation. In short the animal Ikes. These 

 activities are, as we all know, shared by other animals, and some 

 of them by plants also, which grow and repair certain injui'ies — 

 replacing lost parts — and reproduce their land. 



5^ 10. The term usually employed to denote the study of the bodily 

 activities, or functions generally, is Physiology. 



This study is made up of various subordinate inquiries. We 

 may consider the functions of each tissue, of each organ, and of each 

 system of organs. Thus we have, ('.[/., the study of the actions of the 

 system of organs which nourish and support the body : i.e., the 

 study of the function of sustenfation. "\Ve have again the study of 

 that system of organs Avhich serves to continue the race, i.e., the 

 study of the function of reproduction. 



We shall hereafter see that the former function is performed by 

 various organs destined respectively to receive and digest food, to 

 distribute about the body the nutritious matter obtained from it, to 

 breathe and to form or secrete certain products. These functions, 

 therefore, arc those of (1) alimentation, (2) circulation, (3) resjnration 

 and (4) secretion. 



But a creature, such as our t3'pe the cat, not only lives and repro- 

 duces, it is also active, and executes a great number of apparently 

 voluntary and other actions, and has a power of experiencing a 

 variety of sensations. The functions then of (1) mot ion, and {"2) 

 sensation, form other subjects of physiological inquiry. 



The last two functions are called t//c aninuil functiona.* The 

 functions which minister to susteutation and reproduction, as they 

 arc found in all living creatures, plants as well as animals, are 

 called the verjctaticc, or vegetal, functions. 



* Becaiisc sensation does not exist in i spicuona i)owers of motiou are special 

 any plant, while loconaotion ami all cun- | animal eudowiuents. 



