288 American AssociaUon. 



following questions: — -Ist What is a species? 2nd. Are spe- 

 cies permanent ? 3rcl. What is the basis of variations in species ? 

 And first he said, that the idea of a group which is the com- 

 mon definition, was not essential, and indeed tended to confusion. 

 Looking first at inorganic nature they learned that each element 

 was represented by a specific amount or law of force. Thus taking 

 the lightest element as a unit, oxygen would be found ex- 

 pressed by 8, and was of the same vakie in all its compounds. 

 The resultant molecule was still equivalent to a fixed amount, 

 Hence the essential idea of a species is that it corresponds to a 

 specific amount or condition of centrated force defined in the act 

 or law of creation. In the organic world the individual was 

 involved in the germ, which possessed powers of developement 

 to a completed result, and this also corresponded to a measured 

 qnota or specific law of force, though there was no unit by which to 

 measure it, and though there might be difterent kinds of force. 

 The s^me definition of a species would apply here, and thus 

 species v/as in the potential value of the individual whether one or 

 many existed, and the precise nature of the potentiality in each 

 was expressed by its whole progress from the germ to its full 

 expansion. 2nd. As to the permanence of species, it was found in 

 the inorganic world that the element was always the same : oxy- 

 gen was always 8, and all nature was characterised by fixed num- 

 bers. This being so for inorganic nature, must be so everywhere, 

 for the principles which pervaded nature were not of contrariety ; 

 but of unity and universality. If the kingdoms of life were not 

 made from the units which exhibited themselves in their simplest 

 condition — if these units were capable of blending, they would not 

 be units, and life would be but a system of perplexities. It might 

 be seen, too, that the purity of species was guarded in nature» 

 Both in the animal and vegetable kingdom, hybrids were 

 her aversion as far as yet observed. Least of all was it to be 

 expected that the law of permanence, so rigid among plants and 

 the lower animals, should have its main exception in man. Yet if 

 there were more than one species of man, the number of species 

 must become indefinite by intermixture. It would have been a 

 clumsy mode of giving man the control in all the zones of the 

 earth, to have made him of many species capable of hybridization 

 in opposition to the general law of nature. It would have been 

 using for the propagation of the human race, a process which 

 produces impotence aniong aiiimals. It is true that different inor- 



