128 Journal of the Mitchell Society [il/arc/i 



With these considerations bearing on the nature and conduct of 

 courses in General Biology it remains to be stated that an elementary 

 course of this character appears to become increasingly justified by 

 each new large development in Biology. The essential agreements in 

 ultimate structure between animals and plants brought out by Schlei- 

 den and Schwann, by Max Schultze, by the selection theory and other 

 hypotheses of evolution have been extended by more recent studies 

 on chromosomes and on the mechanism of hereditary transmission. 

 For the justification of the already strategic position of General Biol- 

 ogy in the middle-ground between the two great "kingdoms" it is im- 

 portant to realize that none of these great developments, above named, 

 sprang solely from Botany or Zoology as such but always from laws 

 inherent in the nature of both. If we can judge of the future from 

 the past it seems reasonable to predict that the biological generaliza- 

 tions of the twentieth century, I'ike those of the nineteenth, must 

 emerge from similar common sources. 



The General Biology Course gives also a peculiar advantage for 

 the presentation of the facts of symbiosis and of interdependence be- 

 tween plants and animals. This aspect has been developed extensively 

 in the textbook by J. G. Needham, and the emphasis is legitimate, for 

 in nature living forms have not evolved alone but as factors of an 

 interdependent symbiogenetic complex of processes. Further, from 

 a broader physico-chemical world view, in the light of Professor Hen- 

 derson 's work on "The Fitness of the Environment," we gain even 

 a fuller confidence, that as an introduction to the principles of the 

 science and as the most rational type of course for the beginner. Gen- 

 eral Biology is beyond all question superior to distinct courses in 

 Zoology and Botany. 



If it be urged that this type of course is too dependent upon the 

 ability and personality of the teacher the answer is that the success 

 of any course is likewise largely thus dependent. No subject will 

 teach itself. 



Although biological principles in education are not always to be 

 taken literally, as shown by the misuse of the biogenetic law as ap- 

 plied to primary education, there are here applicable suggestive evolu- 

 tionary principles which are of interest. The principal lesson of evolu- 

 tion is not that man is an unfolded amoeba but that all life is one. 

 Further, no evolutionary principle is more important than that the 

 great groups of living forms, surcharged with capacity for adaptive 



