414 The American Naturalist. [May, 
Certain authors who have investigated the digestive process 
(among them Darwin, Gorup, Besanz, Reess and Will) have 
concluded that it is the result of pepsin secreted by the plants. 
Others, as C. Morren, see only a process of rotting and decay. 
Tischutkin in his former paper has reviewed the methods by 
which these various authors have arrived at their results. 
Morren placed on the leaves of Drosera binata Labill. different 
insects and cubes of coagulated egg albumen and observed 
that a few hours afterward the albumen became transparent, 
the angles were rounded off, and after a day or two the pieces 
entirely disappeared. Microscopic examination of the trans- 
parent fragments of albumen revealed the presence of bacteria, 
monads, and filaments of a mycelium which resembled the 
conjugating stage of some species of Mucorineæ. He concludes 
that while this dissolving of the albumen by some absorbent 
principle is possible, the intervention of pepsin is entirely 
problematic. 
Schimper in the Botanische Zeitung for 1882 tells of some 
experiments which he made with Sarracenia purpurea. These 
are of great value because made on plants growing wild in 
Massachusetts. A part of the observations were made on 
insects caught by the plants, and a part by placing pieces of 
meat on the leaves. He found that on stopping up the 
mouths of the leaves at their time of opening and thus pre- 
venting the free entrance of bacteria the digestion took place 
no more rapidly than when the bits of meat were placed in 
pure water, and from this fact he concluded that pepsin was 
not present. He did not test the liquid by chemical means. 
He found great numbers of worms in many of the leaves and 
thinks that they may have something to do in rendering 
organic matter absorbable. 
Hildebrandt in the Botanische Zeitung for 1870 tells of the 
experiments made on the leaves of Dionxa muscipula Ell. an 
on the cups of Sarracenia, Cephalotus and Nepenthes. He 
doubts very much whether the insects caught are of value to 
the plants. “My observations on Dionza muscipula showed 
me that the long legged spiders which are caught in the 
leaves exert an injurious influence upon them. A slimy fluid 
