ADVENTITIOUS BUDS. 161 



Pyriis Japonicay Anemone Japonica^ &c. What are 

 termed suckers, owe their origin to buds formed in this 

 situation. 



If roots be exposed or injured, they will frequently 

 emit buds. The well-known experiment of Duhamel, 

 in which a willow was placed with the branches in the 

 soil and the roots in the air, and emitted new buds from 

 the latter and new roots from the former, depended on 

 this production of adventitious organs of either kind. 



Gardeners often avail themselves of the power that 

 the roots have of producing buds to propagate plants 

 by cuttings of the roots, but in many of these cases 

 the organ "parted" or cut is really an underground 

 stem and not a true root. 



M. Claas Mulder has figured and described a case in 

 the turnip-radish of the unusual formation of a leafy 

 shoot from the root, apparently after injury.^ From 

 the figure it appears as if the low^er portion of the root 

 had been split almost to the extremity, while the upper 

 portion seems to have a central cavity passing through 

 it. From the angle, formed by the split segments 

 below, proceeds a tuft of leaves, some of which appear 

 to have traversed the central cavity and to have 

 emerged from the summit, mingling with the other 

 leaves in that situation. The production of a flower- 

 bud has even been noticed on the root of a species of 

 Impatlens. 



Formation of shoots beneath the cotyledons. The tigellar or 

 axial portion of the embryo plant, as contrasted witli 

 the radicle proper, is very variously developed in 

 different cases.; sometimes it is a mere "collar" bear- 

 ing the cotyledons, while at other times it is of con- 

 siderable size. Generally it does not give origin to 

 shoots or leaves other than the seed-leaves, but occa- 

 sionally shoots may be seen projecting from it below 

 the level of the cotyledons. This happens frequently 

 in seedling plants of Anagallis arvensisy Euphorbia 



' ' Tijdschrift vooor Natiiur. Geschied,' 1836, vol. iii, tab. vii, p. 171. 



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