152 CELL INTELLIGENCE THE CAUSE OF EVOLUTION 



it if it is not the right thing to do. On this point Spencer 

 makes the remark : "That is to say, these literally outer 

 layers of skin are capable of rapidly assuming one an- 

 other's structures and functions when subject to one an- 

 other's conditions. Mucus surfaces normally kept covered, 

 become skin-like if exposed to the air, originally moist, 

 tender to the touch and irritated by the air. The surface 

 gradually becomes covered with a thick, dry cuticle and 

 scarcely more sensitive." The facts seem to be that noth- 

 ing is produced or changed except when it is necessary 

 and for a purpose. It never takes place by chance. We 

 find that differentiation will arise altogether from their 

 method, place and condition of existence ; that every 

 plant, insect, bird or animal is a structure designed to 

 meet certain conditions of life, in the same manner ex- 

 actly as a ship is designed to move over water, an automo- 

 bile over the ground and the airship through the air. 

 Plants and animals have so many structures in common, 

 which over-lap each other in so many ways, that it is im- 

 possible to tell in a great number of cases where the ani- 

 mal commences and the plant ends. 



La Mark classified all creation according to the de- 

 velopment of the brain and nervous system ; such a classi- 

 fication proved later, of course, to be entirely erroneous, 

 as it was discovered later that insects showed intelligence 

 in their particular place in life equal if not superior to any 

 of the higher animals. The cell that builds the little air- 

 ship known as the lightning bug has the knowledge com- 

 pletely mastered of how to produce a light without heat. 

 Hundreds of thousands of dollars have been spent by the 

 most skilled chemists to learn the secret known by the 

 builders of this bug of how to produce a light without 

 heat. We have finally, after spending considerable money 



