322 EE-V. J. T. GULICK ON 



mitted, will multiply the number of characteristica in regard to 

 wlucli divergence takes place. If, for example, tlie pollen of a 

 given variety, vphen i^falling upon the stigma of the same variety 

 or race, is impotent over the pollen of any other variety or race 

 that falls upon the same stigma at the same time, or at a some- 

 what earlier time, what I call Prepotential Segregation will divide 

 the species into two groups that are prevented, for the most part, 

 from intergeneratiug ; and these separate groups, gradually 

 coming under the influence of different degrees, forms, and com- 

 binations of the transforming principles, will in time become 

 strongly characterized species. It is not, however, necessary 

 that all or any of these forms of transformation should cooperate 

 with Segregation in order to produce a distinct species. The 

 accumulated effects of Segregation, unaided by these principles 

 of transformation, would be sufilcient to produce well-defined 

 species ; but it is impossible that they should often remain 

 unaided. 



As the law of Intension is one of the most general of the laws 

 relating to divergent evolution, it is not strange that the prin- 

 ciples through which it is made evident are of a general nature. 

 The marvel is that concerning so wide a law the evidence is so 

 complete. 



Utilitarian and JSTon-Utilitarian Divergence. 



The principles of Suetude and Selection are directly related to 

 the development of utilitarian characters ; but the eff'ects of the 

 other six principles are often not only wanting in, but opposed 

 to, utility. Assimilational Transformation includes redundance of 

 growth, which is not always, as well as economy of growth, which 

 is always, utilitarian. Some of the inherited efi'ects of Stimula- 

 tion and Emotion fortify the constitution against the destructive 

 influences of the environment, while others leave the ofl'spring 

 more exposed than the parent. Unbalanced Elimination, Amal- 

 gamation, and Eecundity may be advantageous, useless, or dis- 

 advantageous. We have, therefore, in these six principles of 

 transformation abundant cause for the introduction of non- 

 utilitarian characters ; and, when accompanied by Independent 

 Greneration, they must be the source of multitudes of non-utili- 

 tarian divergences. In the earlier stages of divergent evolution 

 the non-utilitarian distinctions are more abundant ; for in the 

 later stages multitudes of them are weeded out by economy of 



