608 



BOTANY 



Darlingtonia of the Sierra Nevada. In these plants the petiole of 

 the leaf is developed into a tubular receptacle, more or less com- 

 pletely covered by an overarching lid. This pitcher is often highly 

 colored and conspicuous, and in some species attracts insects by 

 means of a sugary secretion. The insect, entering the interior, can 

 readily descend the walls, which are lined with downward-pointing 



hairs in their upper portion, but are 

 smooth below. The cup is partly 

 filled with a fluid secreted by the 

 plant, and acting to some degree as 



B 



FIG. 476. Nepenthes Veitchii. 

 (After BAILEY.) 



FIG. 477. Drosera intermedia. A, plant, 

 about natural size. B, a leaf, enlarged, 

 which has captured a mosquito, in. 



a digestive fluid ; but the decomposi- 

 tion of the insects which fall into 

 the fluid is largely due to Bacteria, 

 which perhaps aid in putting the 

 decomposing matter into such form 

 that it can be absorbed by the plant. In Darlingtonia and some 

 species of Sarracenia e.g. S. variolaris there are translucent 

 spots in the hooded top of the pitcher, which perhaps prevent the 

 imprisoned insects from noticing the real opening. In Darlingtonia, 

 also, there is a curious forked appendage at the mouth of the pitcher, 

 which may be an attractive body. 



The pitchers of the tropical Nepenthes are produced at the ends 



