126 



elimination of the unfit exercising a directing and delimiting 

 function on the actual forms assumed by organized life, we have 

 the best of Darwinism, neo-Lamarckism, neo-vitalism, Mendelism 

 and the mutation theory." 



The Compositae appear to have been formed with and for 

 the mountains. The facts may be explained on the theory 

 that a vellow Lobelioid, starting as an arborescent scrambler 



Cretaceous 



Fig. I. — Probable evolution of the Compositae (abrikged from James Small). 



about the sources of the Amazon, ascended the Andes shortly 

 after their elevation during the cretaceous period. In the 

 higher altitudes the plant became dwarfed, the flowers and 

 pedicels smaller. Orthogenesis crowded the flowers closer, the 

 anther tube became erect, only a few ovules were developed; 

 in short there arose a form essentially like the alpine Senecio 

 Jacohaea. So close is the affinity that the author must doubt 

 the dictum of De Vries that "great lines of evolution of whole 

 families and even of genera ... lie outside the limits of expe- 

 rimental observation." — Alfred Gundersen, 



