COMPARED WITH THOSE OP ANIMALS. 81 



tial in their character. None of them enjoy the faculty of 

 displacing themselves in toto and removing to another spot 

 more favorable to their growth. When unfavorably located, 

 seeds either perish, or the germination and subsequent 

 growth of the plant is greatly retarded. In a word, volun- 

 tary locomotion exists only in animals. 



That the nutritive functions of animals are affected by 

 nervous influences, many facts abundantly prove. In blush- 

 ing, the nerves evidently affect the blood, which is the grand 

 vehicle of nutritive matter in animals, enlarging the capil- 

 laries and bringing it in an increased flow to the surface; a 

 person affrighted becomes pale, the nerves contracting the 

 capillaries and driving the blood from the countenance. 

 Bad news will affect the appetite, and prevent the healthy 

 action of the digestive organs. The sight of food will pro- 

 duce a flow of the secretion from the salivary glands of the 

 mouth, necessary for its lubrication ; and the excitement 

 created in the mother by the mere presence of the new-born 

 infant, will bring a draught of milk into the breast. Grief 

 will render the eye tearful, or even tearless. There are no 

 such nervous influences to interfere with the nutritive pro- 

 cesses in plants. 



Even the reproductive functions, which in animals are far 

 more intimately associated with the nerves than those of 

 nutrition, in plants, generally speaking, are unmarked by 

 any higher vital phenomena than that which is manifested 

 in the evolution of the other parts of the organism. The 

 fecundation of the germ is effected by an appropriate 

 arrangement of the organs, and the embryo is freed from 

 the ovary by a mechanical rupture of the parts, or by other 

 physical means. The whole process is simply vegetative. 



In some few species, however, such as the barberry 

 (Berberis vulgaris,) and mountain laurel, (Kalmialatifolia,) 



