60 THE AMERICAN BOTANIST 



propagate also non-sexually by budding, but so do' many of 

 the lower animals. In many plants there is regeneration when 

 parts are cut away, but so there is in a great variety of animals. 

 Even their foods are not different. It is true, the plants differs 

 decidedly from the animal in possessing an apparatus for 

 elaborating inorganic substances into starch, sugar, and pro- 

 teids, which the animal consumes, but it makes these substances 

 for its own use, not for the animal. It is sometimes assumed 

 that the inorganic substances, of earth, air and water, are the 

 food of the plants, but such is not the case. The plant depends 

 for its growth on the same nutrient substances as the her- 

 bivorous animals, viz., on starch, sugar, and proteid, which it 

 has stored in every seed and under every growing bud. The 

 phenomena of birth, growth and decay are essentially the 

 same in plants and in animals; but corresponding to higher 

 development, the animal has many special organs either want- 

 ing altogether in the plant, or greatly simplified; it also has 

 flexible cell walls while the plant has rigid cell walls. But 

 both plants and animals respire, both assimilate food sub- 

 stances and oxidize them with resultant work; both require 

 about the same amount of water and mineral salts; both have 

 a circulation of fluids and both secrete and excrete a variety 

 of substances, acid, alkaline, and neutral. The response to 

 stimuli, such a gravity, heat, light, radium, X-ray, electricity, 

 and poisons, is much the same in both groups. In irritable 

 response, plants and animals both obey Weber's Law; that is, 

 to increase a response in an arithmetical ratio, the stimulus 

 must be applied in a geometrical ratio. There is a suggestion. 

 even, of a nervous system in plants since stimuli are passed 

 along certain channels to distant organs, and the movement 

 can be slowed down by cold, increased by heat, or inhibited 

 by poisons applied midway, the response, according to Bose, 

 being not simply hydro-mechanical. Even the idea of locomo- 

 tion does not distinguish animals from plants. Many of the 



