294 REVIEWS. 



and reproduction of each animal, which is strictly physio- 

 logical, and that of the more "general" functions of its 

 internal organs, which is generally recognised as comparative 

 physiology; for, just as since Bichat wrote, we have recog- 

 nised that minute anatomy is general anatomy, so the func- 

 tions of the various organs and tissues of animals are almost 

 always more general, and therefore more important to one 

 who, like M. Bernard, is chiefly interested in human physio- 

 logy, than the functions exhibited by the same animal as an 

 entire organism. But, when it is pretended that the study 

 of the function of respiration is really the study of the beha- 

 viour of red blood discs, we see at once how far wrong an 

 eminent man of science may be led by a narrow and one- 

 sided view of his own subject. 



If what has been stated above be true, it follows that half 

 " zoology" is comparative physiology; and, so far, it will be 

 allowed to be an experimental science, even by M, Bernard ; 

 the other half is descriptive, but not more so than the minute 

 anatomy of the tissues, which is necessary to the most experi- 

 mental and "dominant" physiology, and which has often 

 done duty in text-books and examinations for the real study 

 of animal functions. 



Even physiology, in the strictest sense, is not a purely 

 experimental science. Of the two most brilliant discoveries 

 made by Englishmen, while Sir Charles Bell's was made by 

 direct experiment, that of Harvey was founded on teleo- 

 logical deductions from anatomical facts, and was not con- 

 firmed by actual observation till after his death. Vivisection 

 is not the only way of gaining increased knowledge in phy- 

 siology. What we need in this, as in other so-called experi- 

 mental sciences, is a number of observations — not isolated, 

 but repeated, not made under one, but under many different 

 conditions — mutually checking and controlling each other ; 

 and such a series is often as well attained by observation of 

 the experiments which nature is continually making before 

 our eyes as by of those which we make in our laboratories, 

 more or less clumsily, for ourselves. 



There is, however, another aspect in which zoology, using 

 the term in the most restricted sense, may be ranked with 

 chemistry, physics, and physiology. Besides description of 

 animals, it includes their classification. Now, if we attempt 

 to make this more than a convenient arrangement for the 

 memory, if we try to express by it their true relations, this 

 branch of zoology becomes at once " experimental." As soon 

 as any hypothesis of the way in whicli species have arisen is 

 adopted, every fresh observation of structure, or function, or 



