CALYCIFLOR^ 



209 



or indefinite, usually free, sometimes monadelphous. 



Common plants are lajwabati or Sensitive Plant 

 {Mimosa pudica) ; pani-lajuk {Neptunia oleracea and 

 N. plena) (fig. 181), common water-weeds with sensi- 

 tive leaves, hence called the lajwabati of water, as 

 Mimosa pudica is the lajwabati of land; babla {Acacia 

 arabica), gua-babla {A. Farnesiana), khair {A. Cate- 

 chu), gila {Entada Pur- 

 scBtha D.C.), and sirish 

 {Albizzia Lebbek). 



The familiar instance of 

 the. extreme sensitiveness of 

 the leaves of Mimosa pudica, 

 the Sensitive Plant, is an 

 interesting study (see fig. 

 138). The leaf is pinnate, 

 consisting of a primary axis 

 or petiole, at the end of 

 which are inserted four se- 

 condary axes, to which 

 thickly crowded leaflets are 

 attached right and left. The 

 axes, primary and second- 

 ary, as well as the leaflets, 

 are articulated by well-de- 

 veloped PULVINI or tumid motile apparatus. In the 

 normal state the primary axis stands obliquely up- 

 wards, and the secondary axes with the leaflets are 

 spread almost horizontally. Upon a suitable stimulus 

 or irritation, such as vibration, the leaflets fold up- 

 wards and forwards in pairs; then the secondary axes 

 move laterally, so as to come close together and lie 

 almost parallel; and, lastly, the primary axis droops 

 downwards, taking with it the secondary axes. The 

 behaviour of the leaf is still more curious when a 



(0945) 15 



Fig:. 181. — Pani-lajuk (Xepiimia) 



