CHAPTER XIII. 



CLIMBING AND INSECTIVOROUS PLANTS. 



[My father mentions in his ' Autobiography ' (vol. i. p. 75) 

 that he was led to take up the subject of climbing plants 

 by reading Dr. Gray's paper, " Note on the Coiling of the 

 Tendrils of Plants." * This essay seems to have been read 

 in 1862, but I am only able to guess at the date of the letter 

 in which he asks for a reference to it, so that the precise 

 date of his beginning this work cannot be determined. 



In June 1863 he was certainly at work, and wrote to Sir. J. 

 D. Hooker for information as to previous publications on the 

 subject, being then in ignorance of Palm's and H. v. Mohl's 

 works on climbing plants, both of which were published in 

 1827.] 



C. Darwin to J. D. Hooker. 



Down [June] 25 [1863]. 



My dear Hooker, — I -have been observing pretty care- 

 fully a little fact which has surprised me ; and I want to know 

 from you and Oliver whether it seems new or odd to you, so 

 just tell me whenever you write ; it is a very trifling fact, so do 

 not answer on purpose. 



I have got a plant of Echi?iocystis lobata to observe the 

 irritability of the tendrils described by Asa Gray, and which 

 of course, is plain enough. Having the plant in my study, 

 I have been surprised to find that the uppermost part of each 

 branch (1. e. the stem between the two uppermost leaves ex- 



* ' Proc. Amer. Acad, of Arts and Sciences,' 1858. 



