OF NATURAL HISTORY. 17 



getable motion. It is a native of the Eaft Indies. Its move- 

 ments are not excited by the contat^ of external bodies, but 

 folely by the influence of the fun's rays. The motions oi 

 this plant are confined to the leaves^ which are fupported by 

 long flexible foot ftalks. When the fun fliines, the leaves 

 move brifkly in every direction. Their general motion 

 however, is upward and downward, but they not unfrequently 

 turn almoft round ; and then their footftalks are evidently 

 twifted. Thefe motions go on inceflantly as long as the heat 

 of the fun continues ; but they ceafe during the night, 

 and when the weather is cold and cloudy. Our wonder is 

 excited by the rapidity and conftancy of the movements pe- 

 culiar to this plant. The frequency, however, of limilar 

 motions in other plants, renders it probable that the leaves 

 of all vegetables move, or are agitated by the rays of the 

 fun, though many of thefe movements are too flow for our 

 perception. 



The American plant called dionaea mufdpula^ or Vinus's fiy^ 

 trapi affords another inftance of rapid vegetable motion. Its 

 leaves are jointed, and furnifhed with two rows of flrong prick- 

 les. Their lurfaces are covered with a number of minute 

 glands, which fecrete a Iweet liquor, and allure the approach 

 of flies. When thefe parts are touched by the legs of a fly, 

 the two lobes of the leaf inllantly rife up, the rows of pric- 

 kles lock themfelves fafl together, and fqueeze the unwary 

 animal to death. If a ftraw or a pin be introduced between 

 the lobes the fame motions are excited. 



When a feed is fown in a reverfed pofition, the young root 

 turns downwards to enter the earth, and the ftem bends 

 upward into the air. Confine a young fleni to an inclined 

 pofition, and its extremity will foon alTume its former per- 

 pendicular diredlion. Twifl the branches of any tree in fuch 

 a manner that the inferior furfaces of the leaves are turn- 

 ed towards the fky, and you will, in a iLort tin'ie, per- 



