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(as by the looser being charged with fluid), it then coils as a spring — 

 or in the other case, by both tissues losing their moisture, the denser 

 contracts the most forcibly and the curve is toward that side where it 

 is placed. By the addition of moisture the elasticity of the denser is 

 destroyed, and the filling of the cells of the looser restores the equili- 

 brium and the parts regain their natural position. 



When we consider the nature of this power, — its various degrees from 

 being barely perceptible until it alarms us by the violence of its re- 

 ports, and reflect what its effects are and in what parts of plants it is 

 generally to be observed, which will be the most frequent in the or- 

 gans of reproduction ; one is almost led to believe it to be a power 

 given to plants, which is in some measure the representative of the 

 muscular system in animals : for if in plants we discover any change 

 of place of an entire plant, or of any organ, so as to alter its position 

 or remove it completely from the parent, though it is but a feeble act 

 of locomotion, yet it is performed by this power, and almost the whole 

 of the numerous means of promoting the escape of seeds from the 

 seed-vessel depend on the separation of the parts by means of their 

 peculiarly adapted structures. 



Besides these properties there can be no doubt that this same pow- 

 er is employed under vital agency, in regulating elasticity, expansion 

 of flowers, opening of the anthers for the dispersion of the pollen, and 

 other functions which are hidden from our examination. 



The marked effects which have been mentioned are only a few that 

 have been selected on account of the instances being so well known, 

 but others are to be found with the greatest frequency ; scarcely can 

 a plant be examined in which these actions are not evident in some 

 parts of its structure ; each of which forms but another instance of 

 the wisdom and intelligence displayed in the structure and contri- 

 vances exhibited in the vegetable creation. 



