Hi Laurent. I am not sure one can say the function of the "tops" is to
completely block out any rain, but perhaps to regulate the amount of rain
water getting into the pitcher. I propose this because I have noticed that
the water level decreases in my Nepenthes without filling back up. I
haven't dumped out the contents of a pitcher yet to see if it will fill up
again, but I doubt it would fill up very much. Has anyone observed this?
> Perry Malouf told me that the movements of a crawling insect inside the
> trap could produce this effect. But I'd like to know, then, how the plant
> can feel these movements.
Another excellent question. Perhaps it is not the movement of an insect
but rather a disturbance in the equilibrium of the chemical species in the
liquid. More prey, more bacterial action and hence more enzyme production
ultimately resulting in the absorption of nutrients; assuming of course
Laurent's Nepenthes rely on bacterial aid. Why not then increase nectar
production while everything is already "warmed up" in the pitcher ready
for the next prey?
Paul Burkhardt