130 VIGNETTES FROM NATURE. 



capsule used once to open. In the yellow 

 loosestrife you will find exactly similar 

 marks ; only in that case they are the lines 

 along which the capsule actually splits when 

 ripe ; whereas in the pimpernel they only 

 simulate such a purpose beforehand, while 

 the actual mode of opening is by a transverse 

 division. There can be no doubt at all, 

 therefore, that the pimpernel is really directly 

 descended from an ancestor which closely 

 resembled the woodland loosestrife ; and that 

 the present peculiarity in its method of 

 opening is quite a modern or recently 

 acquired habit. Otherwise, it would not 

 still retain the five valve-marks on the half- 

 ripe capsule so very distinctly as it still does. 

 In every other respect except this one 

 point the woodland loosestrife much more 

 closely resembles the pimpernel than it 

 resembles the other members of its own 

 genus. Both are slender trailing plants, 

 with leaves of much the same character; 

 both have small flowers of the same general 



