Page:Popular Science Monthly Volume 65.djvu/426

422 Here are pitfalls, then, not very unlike those of the American pitcher-plant in their mode of decoying victims and preventing their escape, but far advanced over them in their action, for the digestive juice yields up the nourishing substance of the insect much more rapidly than does the process of decay, and far more economically too, thus increasing the amount of the plant 's food, and thereby its abilities for growth and reproduction.

The closed trap and the pitchered leaf are not the only devices for insect capture which we find among plants; they also possess devices which man has closely paralleled in his invention of fly-paper. These

are, in general, sticky secretions borne either upon a flat leaf surface or on the ends of hairs arising from leaves. The plants possessing snares of this sort are more numerous than those with pitchers, and quite as successful as the latter in obtaining a generous supply of nitrogenous food.

Simplest of this class of the insectivorous plants is the butterwort (Pinguicula), a small annual, not unlike some of our commonest violets in appearance. A dweller in high mountains and the cold bogs of the north, it is particularly well known to every one who has climbed