88 



THE LEAF 



77. Sarracenia purpurea, the Pitcher Plant of 

 the Northern United States. 



surface, their descent aided by the direction of the bristly 



hairs, they have fall- 

 en helplessly into the 

 liquid below. The 

 liquid exudes from 

 the tissues of the 

 leaf itself ; though 

 the spreading hood 

 of Sarracenia pur- 

 purea must catch a 

 certain amount of 

 rain. To what ex- 

 tent the dissolution 

 of the captured 

 insects is promoted 

 by digestive ele- 

 ments produced by 



^^ e Ditcher to what 



extent by ordinary 

 decay, is not certain. It is held, however, that the 

 organic solutions are absorbed and used by the plant. 



154. Insects are caught in another 

 way, and more expertly, by the most 

 extraordinary of all the plants of this 

 country, the Dioncea or Venus's Fly- 

 trap, which grows in the sandy bogs 

 around Wilmington, North Carolina. 

 Here (Fig. 78) each leaf bears at its 

 summit an appendage which opens and 

 shuts, in shape something like a steel 

 trap, and operating much like one. 

 For when open, no sooner does a fly 

 alight on its surface, and brush against 

 any one of the two or three bristles that 

 grow there, than the trap suddenly 

 closes, capturing the intruder. If the fly escapes, the 

 trap soon slowly opens, and is ready for another cap- 

 ture. When retained, the insect is after a time moistened 



