ON THE MORPHOLOGICAL VIEW OF NATURE. 259 



correspondence of parts or organs based not so much on 

 external likeness as on similarity of origin. By admit- 

 ting the latter conception, the idea of origin, the rigidity 

 of the purely structural classification was lost. Morpho- 

 logy became the science, not of fixed, but of flowing 

 forms and structures. It is remarkable that Owen, in 

 following up this line of reasoning, was pre-eminently at- 

 tracted to the oracular writings of Oken, whose influence 

 his great forerunner Cuvier had combated with all his 



pended to the first volume of his 

 ' Hunterian Lectures,' as follows : 

 "'Analogue' A part or organ in 

 one animal which has the same 

 function as another part or organ 

 in a different animal." '"Hom- 

 ologue ' The same organ in dif- 

 erent animals under every variety 

 of form and function." He then 

 goes on to distinguish "special," 

 "general," and "serial" homology. 

 For a history of thought the impor- 

 tant point in all these discussions 

 is that, besides the similarity of 

 structure and the sameness of 

 function, relations and points of 

 comparison of a different kind 

 were introduced ; that these were, 

 with more or less alearness, traced 

 to development ; and that through 

 this the genetic view, the doctrine 

 of descent, was prepared by those 

 who", like Owen, were least ready 

 to accept it when it appeared in a 

 definite form. In the light of this 

 new view, of which the next 

 chapter will treat, the whole vocab- 

 ulary of the older morphologists 

 required recasting. These older 

 views, which traced homology to 

 the existence of definite types, 

 models, or patterns possessing a 

 purely ideal existence, have been 

 termed Platonic, inasmuch as in 

 the philosophy of Plato the exist- 

 ence of a world of ideal forms or 



archetypes served to explain what- 

 ever of order is found in the real 

 world of separate things. " The 

 term ' homology,' " says Prof. Ray 

 Lankester, " belongs to the Platonic 

 school, but is nevertheless used 

 without hesitation by those who 

 reject the views of that school. 

 Prof. Owen . . . would understand 

 by ' homologue ' the same organ 

 in different animals under every 

 variety of form and function. . . . 

 But how can the sameness of an 

 organ under every variety of form 

 and function be established or in- 

 vestigated ? This is, and always 

 has been, the stumbling-block in 

 the study of homologies without 

 the light of Evolutionism ; for, to 

 settle this question of sameness, 

 an ideal ' type ' of a group of 

 organisms under study had to be 

 evolved from the human mind, 

 after study of the component 

 members' of the group ; and then 

 it could be asserted that organs 

 might be said to be the ' same ' 

 hi two animals which had a 

 common representation in the 

 ideal type " (' Annals and Mag. 

 of Natural History," 4th series, 

 vol. vi., 1870, p. 34, &c.) See also 

 Huxley in ' Life of Owen,' vol. ii. 

 p. 303, &c. ; and J. Arthur Thom- 

 son, ' The Science of Life, ' p. 32 

 (1899). 



