Page:Popular Science Monthly Volume 65.djvu/427

Rh about in the Alps. The leaves are broad and undivided, slightly inrolled at the edges and coaled on the upper surface with a sticky slime exuded from minute groups of glandular cells. An insect alighting on the leaf is can-lit and held by the sticky secretion, and the more it struggles to escape the more firmly is it held and the more completely does its whole body become involved. If the insect has chanced to alight near the edge of the leaf the inrolled margin will roll still

further so as to cover it completely, but whether near the edge or not, there is something in the contact of this available food which causes the excretion of juice to be so abundantly renewed as to be sure to envelop the insect. In the renewed excretion there is to be found a digestive principle such as occurs in the pitchers of the East Indian pitcher-plant, so the captured prey, soon smothered to death, is also rapidly consumed and its essence carried into the leaves by means of the glandular secreting cells.

It is of interest that the only case in which any of the insectivorous plants have been found of practical use is in connection with the presence of the digestive juice in the butterwort. There is associated