Thoughts on Species. 373 



of a numerical basis to a cohesive attraction ; in the laws of light 

 heat, and sound. Indeed the whole constitution of inorganic 

 nature, and of our minds with reference to nature, as Professor 

 Pierce has well illustrated, involves fixed numbers ; and the uni- 

 verse is not only based on mathematics, but on finite determinate 

 numbers in the very natures of all its elemental forces. Thus 

 the temple of nature is made, we may say, of hewn and mea- 

 sured stones, so that, although reaching to the heavens, we may 

 measure and thus use the finite to rise toward the infinite. 



This being true for inorganic nature, it is necessarily the law 

 for all nature, for the ideas that pervade the universe are not 

 ideas of contrariety but of unity and universality beneath and 

 through diversity. 



The units of the inorganic world, are the weighed elements 

 and their definite compounds or their molecules. The units of 

 the organic are sjjecies which exhibit themselves in their simplest 

 condition in their^ germ-cell state. The kingdoms of life in all 

 their magnificent proportions are made from these units. Were 

 these units capable of blending with one another indefinitely, 

 they would no longer be units, and species could not be recog- 

 nized. The system of life would be a maze of complexities ; 

 and whatever its grandeur to a being that could comprehend the 

 infinite, it would be unintelligible chaos to man. The very beau- 

 ties that might charm the soul would tend to engender hopeless 

 despair in the thoughtful mind, instead of supplying his aspira- 

 tions with eternal and ever-expanding truth. It would be to 

 man the temple of nature fused over its whole surface and 

 through its structure, without a line the mind could mea*sure or 

 comprehend. 



Looking to facts in nature, we see accordingly every where, 

 that the purity of species has been guarded with great precision. 

 It strikes us naturally with wonder, that even in senseless plants, 

 without the emotional repugnance of instinct, and with repro- 

 ductive organs that are all outside, the free winds being often 

 the means of transmission there should be rigid law sustained 

 against intermixture. The supposed cases of perpetuated fertile 

 hybridity are so exceedingly few as almost to condemn them- 

 selves, as no true examples of an abnormity so abhorrent to the 

 system. They violate a principle so essential to the integrity of 

 the plant-kingdom, and so opposed to nature's whole plan, that 

 we rightly demand long and careful study before admitting the 

 exception. 



