206 Rev. P. Keith on Phytological Errors, with Admonitions. 



to account for certain phsenomena of vegetable life, and hence 

 they assumed the aid of susceptibilities of a higher order, — sus- 

 ceptibilities which in the animal subject are termed cerebral. 

 Yet the leading advocates of this opinion have not been no- 

 vices ; they have not been men of mean reputation, whether 

 in literature or in science ; they did not take up the doctrine 

 at random ; they took it up deliberately and advisedly, and 

 hence their opinions are entitled to our respectful considera- 

 tion. Among them we find the names of Bonnet, Watson, 

 Percival, Darwin, Smith. We do not say that M. De Can- 

 dolle's notice of them is not respectful; but he regards the 

 doctrine as supported more by arguments drawn from imagi- 

 nation and feeling, than from reason and experience, that is, 

 from the heart rather than from the head*; and whether this 

 implies anything of a compliment, we leave the reader to de- 

 termine. 



I find that my name is associated, in a foot note, with that 

 of Bonnet, Percival, and Smith, not for having defended the 

 doctrine of vegetable sensibility, I presume, for that I evi- 

 dently controverted, but for having mooted the question in 

 my System of Physiological Botany, and for maintaining, or 

 seeming to maintain, a doctrine that may be said to imply 

 sensation, namely, that of a vegetable instinct. At a loss to 

 account for the singular, and hitherto inexplicable fact of the 

 irresistible descent of the radicle, in the process of germina- 

 tion, through the intervention of any cause, whether chemical 

 or mechanical merely, I thought it was not absurd to suppose 

 in the vegetable subject, the existence and agency of a cause 

 analogous to that of instinct in the animal subject, but not 

 identical with itf . But although a zoologist is allowed the 

 aid of instinct to account for the unaccountables of the animal 

 ceconomy, yet let me admonish the phytologist who has any 

 respect for the opinion of the critics, to beware how he lays 

 claim to the aid of an analogous principle to account for 

 the unaccountables of the vegetable ceconomy. He will be 

 set down immediately as a fool or a blockhead. His case is 

 without remedy, and his sentence without mercy. He will 

 be told that the doctrine "is palpably inadmissible;" that 

 " it is absurd;" and that " it is merely a betraying of his 

 ignorance of the cause." Did Newton know the cause 

 which he points out to our notice by the term gravitation ? 



* Phys. Veget., torn. i. p. 29. 



t [Agreeing entirely with Mr. Keith in this view of the subject, we may 

 add, further, (adopting Maclean's distinction of relations of analogy from 

 those of affinity, and employing a new word much wanted,) that this vege- 

 table principle, though strictly analogous to instinct, is not merely not iden- 

 tical but not even affinal with it. — E. W. 13.] 



