Rensselaer Republican, Volume 26, Number 32, Rensselaer, Jasper County, 5 April 1894 — THEY EAT INSECTS. [ARTICLE]

THEY EAT INSECTS.

Flowers That Catch, Devour and Digest Insects Daily. Many Diflbrent Species—Sketch or the Growth of the Pitcher Plant in the North and South and How Its Victims Are Trapped. Fifteen years ago scientists. first learned with certainty that pitcher plants, among other varieties, were carnivorous, i. e.. that they caught and digested insects. Professor Wilson has discovered that this power can be iost by a kind of retrogression; and he has found a species which, though it still catches insects, has no longer a stomach in which to digest them. No investigation of -these curious plants by mechanical analysis had yet taken place and it was only fifteen years ago that three German botanists detected a peptone-forming ferment in certain plants. Dr. Wilson has confined most of his attention to the genus sarraeenica, which has eight different varieties of insect-catching plants. One of these is found in Massachusetts, the rest in the southern states. During the course of Ths Trivestigatibns the professor spent a summer in the cranberry marshes of Massachusetts, where the northern variety is most plentiful, a summer in North Carolina and a winter and spring on the Gulf coast of Florida.

The sarraeenica plant has leaves shaped like holiow cones. The top or mouth of each cone has over it an oval flap. Along the outside of each leaf are glands which exude a sweet liquid. Feeding from this the insects follow the glands upwards till they re ch the opening at the top. The edge of the interior and the inner walls are as smooth as glass, so that once having slipped over the edge there is nothing to stop the victim’s fall to the very bottom of the cone. Further down there are on the inside coarse hairs pointing downward which botanists say utterly prevent insects from crawling up again. Near the bottom of the cone, inside, are glands which exude another liquid so freely as to till sometimes, in a short lime, from an inch and a hnlf to two inches of its interior cavity. When this liquid covers’ the snared' victims' it automatically acidulates, a ferment' takes place- and everything but the hard shells and bones of the insects la absorbed. In the southern plant the leafy flap above the core bends over to cover the aperture so as to keep out rain and water.

Noticing while in the cranberry region of Massachusetts th it the flap of the plant there stood straight up so bs to admit the rain water, Dr. Wilson determined to investigate the matter. Accordingly he procured bell jars ana covered a number of pitcher plants with these so as to keep out the rain. Upon turning them over he found each cone partially full of the curious liquid which the inner glands exude. Taking samples of this fluid from a number of leaves he found that it was not acid. Arguing, however, that the acidulation might not have taken place, the professor added an acid and then placed in the preparation several pieces of nitrogenous substances. After soaking in the liquid some time he examined them, but the microscope showed no eating away of the edges which would mark the digestive process. Chemical analysis showed only the faintest trace of pepsin, the digesting principle of the animal stomach. Impelled by curiosity to continue his investigations, Dr. Wilson found that the Massachusetts plant had no complete honey glands on the outside of its leaves, but only the rudiments of them. It still caught some insects, but their bodies, unaffected chemically, simply remained in the internal cavity covered by a mixture of water and the plant’s exudation until they rotted away, when, doubtless, some of their parts were absorbed by the leaves.

Here, then, was a variety of the pitcher pin nt which had retrograded from some unknown cause and had lost the use of some of its organs. In general shape this northern plant closely resembles its southern sister. Its hood only is thrown back, while that of the other variety is inclined forward over the aperture of the cone. The early seed leaves of both varieties are identical, a proof. Dr. Wilson thinks, of their both having been originally of the same plate. This curious loss of organic power in the Northern pitcher plant the pro-fe-sor only attempts to explain suggestively. It has been noticed that the Southern pitcher plant, the Sarracenia variolaria, as it is called, maintains in iis stomach, while digesting, about the same temperature as that of the ; nimal stomach, i. e.. nine-ty-eight degrees. Dr. Wilson suggests that the pitcher plant, when carried north to Massachusetts, found there a climate so cold that its organ could not raise the temperature of its stomach to lhe necessary heat. Thus, gradually, it has loot the use of its glands through non-use. The Pinguieulla plant, another insecttivorous plant, has been used by Scandinavian farmers and peasants to curdle milk.