J \irictu-s. 



149 



tion to the animal kingdom, not only in counteract- 

 ing the action of animals on the air and in furnish- 

 ing them with food, but also in their adaptation to 

 the structure and instinct of animals, completing, as 

 they often do by their own growth, in a specific 

 manner, the work which the instinct of the animal 

 commenced. It was shown that the structure of the 

 insect, its instinct, and the nature of the plant growth, 

 are all three often needed to complete the relation of 

 the animal and the plant to the world, so that certain v 



tea in both kingdoms may be preserved. 

 There still remains another characteristic of or- 

 ganic beings that has given rise to much discussion 

 among scientific men. I refer to the production of 

 varieties, or different kinds, from the same stock. 

 The fact is not only acknowledged, but modified 

 forms are springing up almost every year in the 

 animal and vegetable kingdoms. We do not pro- 

 pose to discuss the scientific tests that are proposed 

 for distinguishing species from varieties ; but we 

 wish to show that the power of producing varieties 

 is one of the means by which organic beings are 

 better fitted to the world, and to the wants of man, 

 and that in the nature and final results of many of / 

 these changes it becomes apparent that the wis- 

 dom of their production cannot be vindicated on 

 any other supposition than that they were made 

 ivith direct reference to man. This might involve 

 the whole discussion of what constitutes a species, 

 and how species come into existence. We have not 

 time to enter fully upon that discussion. As to the 



