HOW CERTAIN PLANTS CAPTURE INSECTS. 45 



considerable force to open the trap. If nothing is caught the trap presently 

 reopens of itself and is ready for another attempt. When a fly or any similar 

 insect is captured it is retained until it perishes, — is killed, indeed, and con- 

 sumed ; after which it opens for another capture. But after the first or second it 

 acts sluggishly and feebly, it ages and hardens, at length loses its sensibility, and 

 slowly decays. 



99. It cannot be supposed that plants, like boys, catch flies for pastime or in 

 objectless wantonness. Living beings though they are, yet they are not of a suf- 

 ficiently high order for that. It is equally incredible that such an exquisite 

 apparatus as this should be purposeless. And in the present case the evidence of 

 the purpose and of the meaning of the strange action is wellnigh complete. 

 The face of this living trap is thickly sprinkled with glands immersed in its tex- 

 ture, of elaborate structure under the microscope, but large enough to be clearly 

 discerned with a hand lens ; these glands, soon after an insect is closed upon, give 

 out a saliva-like liquid, which moistens the insect, and in a short time (within a 

 week or two) dissolves all its soft parts, — digests them, we must believe ; and the 

 liquid, with the animal matter it has dissolved, is re-absorbed into the leaf ! We 

 are forced to conclude that, in addition to the ordinary faculties and function of 

 a vegetable, this plant is really carnivorous.* 



100. That, while all plants are food for animals, some few should, in turn and 

 to some extent, feed upon them, will appear more credible when it is considered 

 that whole tribes of plants of the lowest grade (Mould-Fungi and the like) habit- 

 ually feed upon living plants and living animals, or upon their juices when dead. 

 An account of them would make a volume of itself, and an interesting one. But 

 all goes to show that the instances of extraordinary behavior which have been 



• Ellis, who first described the JDiorma in full, and gave it this name noticed the liquid secretion and 

 the glands that produce it, but thought that it was given out while the trap was open and as a lure to 

 insects : he expressed his belief that the leaves caught insects for the purpose of nutrition. Linnaeus 

 appears to have doubted this ; he omitted all account of the fluid, and gave a more humane, but incor- 

 rect, version of the plant's behavior, stating that the trap holds the insect only while it struggles, but 

 releases it on becoming quiet : and this statement has been commonly adopted. Elliott merely copied 

 the description by Linn^us. The Rev. Dr. M. A. Curtis of North Carolina (just deceased) gave a 

 more correct account about thirty years ago. Recently Mr. William M. Canby of Delaware has pub- 

 lished some vei*y interesting observations and experiments ; which show that the liquid is a sort of gas- 

 tric juice, exuded after the capture. He also fed the leaves with morsels of raw beef, and found that 

 these in most instances were mainly dissolved in the juice, which then disappeared, evidently by ab- 

 sorption. Similar observations and experiments made by Mr. Darwin are still unpublished. 



cj- p. >-/<4. 



