FIELD BOOK OF PONDS AND STREAMS 



common horseradish which like water cress is also a table 

 viand. 



Water cress (Fig. ']']) may grow entirely submerged but in 

 summer it more frequently stands 6 to 8 inches above the 

 surface of shallow water and its branching stems spread out 

 and take root like runners on the bottom. The inconspicu- 

 ous white flowers have four petals forming the cross, a family 

 characteristic of the Cruciferce. In winter its bushy rosettes 

 make splashes of verdant green in spring-fed brooks. 



Occurrence. — Springs and brooks; frequent and locally 

 abundant. Blooms June-July. Generally distributed over 

 the country, in the eastern states southward to Virginia. 



Pitcher-plants — Sarraceniacece 



Common pitcher-plant, Sarracenia purpurea. — Pitcher- 

 plants (Fig. 78) grow in peat bogs where their red-green pitch- 

 ers usually rise out of beds of pale sphagnum moss. Their 

 leaves are true pitchers which hold water and they can gener- 

 ally be found partly full of it from the rain. They are 4 to 

 8 inches long, green, with dark red veins, streaked with what 

 Schuyler Mathews has called "raw-meat coloring," and 

 have a tough papery texture. The flaring lip of the pitcher 

 is heavily streaked and is covered with stiff hairs which all 

 point toward the water; insects which pass over them fall 

 down into it, finally drown there, and their decomposing 

 bodies are absorbed by the plant. The curiously shaped 

 flower is green and maroon-red, like the leaves. Its 4 or 5 

 red-lined sepals curve loosely over the green petals that fit 

 about the pistil. This is umbrella-shaped and its stigmatic 

 surface — the inside of the umbrella — is turned upward be- 

 neath sepals and petals which protect it from ever^'thmg 

 but insects. 



Common names of pitcher-plants show how playful and how 

 dangerous they have always appeared, — whippoorwill's 



96 



