— 102 —1 



particularly evident ia compound or pinnated leaves. 



The winged leaves of the leguminouse tribe, acted 

 upon by the heat of the sun, rise vertically and iorm 

 a right angle with the common footstalk, the lobes or 

 lesser leaves clinging together by their upper surface. 

 Simple leaves as " Herbe h, paniers'' Urenalobata 

 when exposed to the sun, become concave. Winged 

 leaves, in a close, moist, and cloudy atmosphere, may 

 be found extended along the common footstalk ; and 

 after the sun sets, they have vertically downward, 

 closed together by the lower surface, like the leaves 

 of a book. If there is an odd lobe at the extremity, 

 it folds upon itself until it reaches the first pair of 

 leaves in its nighbourhood. The simple leaves of 

 bastard and fever-few are good examples. In trefoil, 

 lucerne, and lotus they unite by their extremities, and 

 form a cavity of protection from the chill of the night 

 season. According to Mr Duhamel, this muscular 

 motion is, in sensitive plants, evinced in the two forms 

 of natural and artificial ; warm vapors causing the one, 

 and external agencies, such as touching or shaking 

 causing the other. The muscular motion of the sen*- 

 sitive plants is laid open to our inspection, and is an 

 instance of extreme contractile force. At the lightest 

 touch of the hand they move, close their leaves, and 

 bend their branches, until a sympathetic agitation 

 extends throughout a whole savanna. 



We have also in Mauritius sensitive plants -, for 

 instance Mimosa pudica-—yfh.Qn it is touched, or even 



