BOTANICAL GAZETTE. 14S 



sn])ply, which I will exc'-:ange for U. S. species not in my herbarium, 

 or will sell at ten cents a specimen. — J. \V. Chicki:rin(;. 



Carnivorous Plants. — The advance of science and of human 

 insight into the workings of Nature compel us to admit what seems 

 at fir-^t almost incretlible, diat it i- as natural and normal fur some 

 j)lants to derive their su-^tcnance from the animal tissues by a true pro- 

 cess of feeding, as it is for the animal to feel u|)on plants and gain 

 maturity and strength thereby. 



The fact tlial certain plants, such as Drosera, Dwrnea, Sarracetiia, 

 Utriciilaria and others, obtain at least a portion of their nourishment 

 from animal food by process of digestion, absorption and assimilation, 

 has been dcveloijed more during the last generation than at any pre- 

 vious time, altlioLigh the peculiarities of one of these plants were 

 known and noted during the latter part of the eighteenth century. 

 Dr. Darwin tells us that the oldest and most valuable j)aper published 

 previous to i860 was written by Dr. Roth in 1782. Much has been 

 recorded, in a general way. in our various journals, concerning these 

 plants, but only a small jjroportion of these papers are of much value. 



However, interesting as the discussion of the bibliography of this 

 subject in its various relations and a review of the arguments both for 

 and against the carnivorous characters of these plants, would be, it is 

 noi my intention to enter into a consideration of the general subject, 

 e\en if space would permit, but to simply record my ex])eriments anci 

 observations upon the interestmg division of these plants — the genus 

 Sanacenia nnd the family Droscracccc. For an extended review the 

 reader is referred to Darwin's work on the "Insectivorous Plants," 

 and also to iirticles in Gray's Darwiniana. 



It is the intention to publish these records in series, divided ac- 

 cording to the time and purpose of experimenting and observations. 



At the head of each series notes explanatory in general of all the 

 experiments enimierated will be given. 



Skriks I. Experiments on Dru>.era roll/ ndi folia. 



General obsen'aiions. The [jlants upon which experiments were 

 instituted in this set were Uiider cultivation. The surrounding condi- 

 tions were, as near as it was possible to make them, the same as those 

 in which they grow naturally. 



The amount of light, moisture and air was regulated with great 

 care. The plants were wate'ed at 8 a. m. and 6 p. m., daily, 

 throughout the entire time of experimenting. It is worthy of note 

 that the plants blossomed also during this time 



As to the size of the leaves and the general vigor of the plants, 

 they were \\\t Jiucsl specimens that I could find. They were obtained 

 at a lake, three miles west of Ann Arbor, Mich. 



ExTKRiMENT No. I. — A piece of an angle worm was placed 

 upon the center of a leaf at 2 p. ni., June 4th, 1879. 

 15 min. no change. 



30 " submarginal tentacles inflecting and a few nearest the sub- 

 stance were touching it. ♦ 



