A section of a young flower of Sarracenia leucophylla. The numerous orange stamens are full of pollen. The umbrella-shaped stigma, one edge cut away here, is lined with small short hairs and drops of liquid. These hairs and liquid are involved in catching of the pollen grains. Each of the petals (not yet turned crimson here) curves around the edge of the umbrella-like stigma in an S-shaped fashion. An insect entering this flower must be large and strong enough to force back the petals and crawl in, thereby contacting the pollen or the stigma surfaces.
The throat of a Sarracenia leucophylla pitcher has a reddish shiny rim that evidently attracts insects, particularly in view of the whitish area of the pitcher leaf that contrast with it. The red-purple network pattern overlies the major veins in the leaf. At left is a purple and green wing-like structure that represents the fused margins of the leaf.
A close-up of the outside of the pitcher leaf, near the throat. The white patterns probably are attractive to insects by their brightness. Green areas are also present. White and purple patterns decrease toward the bottom of the leaf, most of the tubular portion of which is green.
Here's the lid of the pitcher of Saracenia leucophylla, showing the surface that overarches the throat. Notice the downward-pointing hairs. These hairs tend to make insects walk downward into the pitcher, preventing them from walking back upwards and out of the pitcher.
Uniquely among insects, the Exyra moths that live in Sarracenia pitchers are not affected by the downwardly-pointing hairs on the inside of the pitchers. The Exyra moths spend their lives within the pitcher, feeding on the leaf tissues as caterpillars.
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