22 



MANUAL OF BOTANY 



number of ring-like expansions on its surface,,as in Ipecacuanlia, 

 it is annulated {fig, 32). 



As to their duration, roots may be classified as annual, 

 biemiial, or perennial. 



Fig. 26. Fie. 27. 



Fig. 26. Tubercular roots of au Orchis. Fiy. 27. Palmated tubercules of 



au Orcliis. 



Fie. 28. 



Fie. 29. 



Fig. 28. Fasciculated roots of the Dahlia. Fig. 29. Nodulose root of the 



common Dropwort (-Spinea FilipendaUi). 



1. Annual Boots. — These are produced by plants which grow 

 from seed, flower, and die the same year in which they are 



