222 The Science of Life. 



which they cannot make clear enough to win conviction 

 from their fellows. 



Gottfried Reinhold Treviranus (1776-1837) shares with 

 Lamarck the credit of coining" the useful word Biology 

 (1802), and is chiefly noteworthy for his analysis of the 

 relations between organisms and their environment. 

 He had in some measure that vivid realization of the 

 interactions in nature which was so characteristic of 

 Charles Darwin, and attained to a firm grasp of some 

 other important biological ideas, such as compensation 

 of growth, functional modification, environmental modi- 

 fication, the relation between fecundity and struggle, 

 environmental elimination, and so on. On the other 

 hand, he weakened his general evolution idea by ac- 

 cepting the myth of occasional spontaneous generation 

 even in higher forms of life. Occasionally Lamarckian, 

 he believed especially in the modifying influence of 

 environment, and the following sentence is representa- 

 tive: " In every living being there exists the capability 

 of an endless variety of form-assumption ; each possesses 

 the power to adapt its organization to the changes of 

 the outer world, and it is this power, put into action by 

 the change of the universe, that has raised the simple 

 zoophytes of the primitive world to continually higher 

 stages of organization, and has introduced a countless 

 variety of species into animate nature ". 



Etienne Geoffrey St. Hilaire (1772-1844) was a pupil 

 of Buffon and a colleague of Lamarck, and like so many 

 of his contemporaries was greatly influenced by Schelling. 

 As a champion of the "unity of plan" doctrine he en- 

 gaged in a famous argument with Cuvier before the 

 French Academy of Sciences (1830), in which the pro- 

 gressive party was for the first time defeated. Follow- 

 ing Buffon rather than Lamarck, he maintained the 

 importance of environmental modifications and believed 

 in their transmission, but his most distinctive doctrine, 

 to which he was probably led by his studies in tera- 

 tology, was that great changes might be brought about 

 suddenly, as it were by leaps and bounds in develop- 

 ment. By this anticipation of what is now called 

 saltatory evolution or discontinuous variation he was 



