194 



BOTANY. 



is firmly held, when a digestive process, similar to that in 

 Dioncea, takes place. This curious habit is probably to be 

 explained from the position where the plant grows, the roots 

 being in water where there does not seem to be a sufficient 

 supply of nitrogenous matter for the wants of the plant, which 

 supplements the supply from the bodies of the captured insects. 

 Similar in their habits, but differing much in appearance 

 from the sundews, are the pitcher-plants (Sarraceniacece), of 

 which one species (Sarracenia purpurea) is very common in 



B 



FIG. 105. Types of Aphanocyclse (Cistiftorse) . A, B, leaves of the pitcher- 

 plant, Sarracenia (Sarraceniacese,) . A, from the side; B, from in front, x %. 

 C, St. John's-wort (Hypericum), x y 2 . /), a flower, x 1. E, the pistil, x 2. 



Or, cross-section of the ovary, x 4. H, diagram of the flower. 



peat bogs throughout the northern United States. In this 

 species (Fig. 105, A, -B), the leaves form a rosette, from the 

 centre of which arises in early summer a tall stalk bearing a 

 single, large, nodding, dark-reddish flower with a curious 

 umbrella-shaped pistil. The leaf stalk is hollow and swollen, 

 with a broad wing on one side, and the blade of the leaf 

 forms a sort of hood at the top. The interior of the pitcher is 

 covered above with stiff, downward-pointing hairs, while below 

 it is very smooth. Insects readily enter the pitcher, but on 



