This section is from the book "The Gardener's Monthly And Horticulturist V24", by Thomas Meehan. See also: Four-Season Harvest: Organic Vegetables from Your Home Garden All Year Long.
I have just read your article on Nepenthes rajah. My attention has been particularly directed to the statement, "But no one appears to have noticed that the Nepenthes catch insects, and Darwin makes no mention of them among his ' Insectivorous Plants.' "
My impression is, that I examined at least fifty pitchers last season, and found insects in all of them. But to make sure of my position in this matter, I went into the stove house this morning and examined six pitchers taken promiscuously from six different plants which are suspended from the rafters of the house. The first pitcher (N. laevis), contained eight dead flies. The second, a hybrid, had two centipedes in it. The third had three flies, a blue-bottle fly, two centipedes, an insect I did not recognize, and several mosquitoes. The remaining three had combinations of the above-named insects in them. They had evidently been drowned in the liquid secretion found in the bottom of the pitchers.
I have long since come to the conclusion that a moist atmosphere, with a temperature ranging from 85° to 100°, Fahrenheit, has more to do with the size of the pitchers than anything else.