134f Vegetable Physiology. 



separated the radiculum of a Ficia Paba carefully from the 

 cotyledons, and found, to my great surprise, that the young 

 plant continued to grow, although it suffered apparently a 

 great check, and a new set of roots began to make their ap- 

 pearance. 



This experiment sufficiently showed me that the young 

 plants have the power of renovating their roots, as long as the 

 cotyledons are left untouched. 



I was now desirous to know what effect it would have on 

 the life of the individual, if the caudex ascendens were cutoff. 

 To gi'atify my desire, I deprived a Ficia jpaba of its caudex, 

 which was about 2 in. high, and two little caudices shot forth, 

 out of the corners of the cotyledons, one of which took the 

 lead, and grew fast, but rather Aveakly ; and, on nearer examin- 

 ation of a bean, I perceived two buds, one in each corner of 

 the cotyledons, which our wise Creator did certainly make for 

 no other purpose but that, if the first grown caudex happen to be 

 destroyed by birds or other animals, another should rise in its 

 place, and supply the loss of the first. But, in the last case, 

 the roots grew to an uncommon size, and filled the whole pot. 

 After all this, I turned the cotyledons of a germinated kidney- 

 bean downwards, and the roots upwards, and, in a short time, 

 the roots inclined towards the soil, and showed an inclination 

 to resume their former position ; and I have no doubt, that 

 if I had continued my observations on it, I should have 

 found the roots to take hold of the ground again, and turn 

 the cotyledons upwards : but my experiment was limited 

 to the question whether the plant can continue to be alive 

 when in this position, and I found the bean, after a lapse of 

 a week, in the same state of health as when I first planted it ; 

 which shows clearly that the cotyledons are able to absorb 

 moisture through their veins, for the nourishment of the 

 plant, also when its growth is already advanced. 



The determination whether this last phenomenon of the 

 root's inclination towards the soil can be called instinct, 

 or whether it is a mere process of gravitation, I must leave to 

 you and to your readers, who are abler physiologists than 

 myself. 



Should these experiments be thought deserving a place in 

 one of your publications, I shall be highly gratified. 



1 remain, Sir, &c. 

 Kent, Sept. 30. 1828. W. Hertz. 



