The Living Machine 



307 



by appropriate staining, and are connected on the one hand 

 with the flagella or cilia and on the other with certain deeply 

 staining granules in the body of the animal. To operate on 

 creatures less than 1/150 inch in length is a surgical 

 11 stunt" of no small difficulty. Yet this has been done and 

 these delicate fibrils cut, with the resultant cessation of move- 

 ment of the connected flagella. It is clear then that these 

 fibrils represent a primitive nerve-muscle structure such as 

 occurs in more differentiated form in some of the simpler of 

 the many-celled animals. 



The ability of higher plants to respond to stimuli is a 



COMPASS PLANTS AS SEEN FROM DIFFERENT POSITIONS 

 From Kerner (translation by Oliver), "Natural History of Plants," 

 Henry Holt and Company. 



Print furnished by Conrad Lantern Slide Company, Chicago. 



matter of common knowledge. We place a plant in our win- 

 dow and soon leaves and stems are bending toward the light. 

 The compass plant is a devoted worshipper of the sun. In 

 the dawn it turns its opening flowers eastward to greet the 

 rising sun, while at eventide they face the west attendant 

 on its setting. The mold Pilobolus grows upon horse 

 manure. When its spores ripen they are thrown by the plant 

 with considerable force, surrounded by the spore cases, in 

 the direction of the light. If a little fresh horse manure be 

 placed in a box with a small window, the filaments of the 

 mold turn toward the window, and as the spores ripen 

 they are thrown in their cases against the window to which 

 they adhere. A tree is felled by a land-slide or a tornado 



