CHAP. I.] 



INTRODUCTORY. 



11 



Yet another and a somewhat peculiar study, is the study of 

 development. It is a study at once morphological and physiological. 

 For it is the study of the changes which the animal passes through 

 in proceeding from its first condition, as a germ, to its adult stage 

 of existence. It is, therefore, a study of form and a study of an 

 active process both together. 



It is also desirable not only to note the function of each organ 

 and set of organs, but also to consider the activity of the animal as 

 a whole the physiology of t/te individual or Psychology. 



11. But we shall be quite unable to answer the question, What 

 is a cat ? if we do not learn the relations in which it stands to other 

 living creatures its position in the general scheme of things : in 

 other words, the cat's place in nature. 



We must therefore compare the cat with all other living creatures ; 

 but especially with those which resemble it the more nearly. But 

 to do this we must first understand more or less what the general 

 scheme of organic nature is, that is to say, we must learn something 

 of the arrangement and classification of living beings, i.e., of the 

 science of Taxonomy. 



12. Every animal and plant (and therefore, the cat and the cat 

 tribe) has certain definite relations to space and time. Its geo- 

 graphical distribution and its past history, as shown by fossil remains, 

 also form indispensable matters of inquiry, and respectively pertain 

 to the sciences of Organic Geography and Palaeontology. But every 

 living creature has also relations with other living creatures, which may 

 tend to destroy it or indirectly to aid it, and the various physical forces 

 and conditions exercise their several influences upon it. The study 

 of all these complex relations to time, space, physical forces, other 

 organisms, and to surrounding conditions generally, constitutes the 

 science of Hexicology* 



13. But there is yet one more inquiry, without which any 

 modern work on zoology would be quite incomplete, and that is a 

 genealogical investigation, the prosecution of which pertains to the 

 science of Phytogeny. This science (assuming the truth of the 

 doctrine of evolution) f investigates the evidence as to the various 

 ancestral forms through which any now existing organism has 

 probably passed in its descent from the most remote organisms 

 which can, with any degree of probability, be regarded as its an- 

 cestors. We must then, finally, endeavour to gain what light we 

 may as to the first origin of that form of life which has been chosen 

 for study in other words we must investigate the cat's probable 

 pedigree. 



14. It appears to the writer that the study of the cat's anatomy 

 and physiology may be best pursued by considering the function 



* ts habit, state, or condition. 



t The doctrine of evolution teaches 

 that each existing kind of animal or 

 plant was originally derived by a natural 



process of generation from other animals 

 or plants more or less different in kind 

 from it. 



