188 



PRACTICAL BOTANY. 



remembered that the stem is an 

 underground rootstock, or rhi- 

 zome, and that what is appar- 

 ently an aerial stem is really 

 the petiole, or stipe, of the leaf. 

 Care should be taken to injure 

 the rhizome as little as possible 

 in removing it from the ground. 

 1. With the naked eye make 

 an examination of an entire 

 plant. What is the color of 

 the rhizome? Notice the lat- 

 eral ridges. Does the rhizome 

 branch? How many leaf stalks 

 grow on a branch? Where on 

 the rhizomes are the leaf stalks 

 borne ? Do you find remains 

 of the leaves of previous years 

 still attached to the rhizome ? 

 Notice the apical bud at the 

 end of the rhizome. If the speci- 

 men was dug up in the spring, 

 the apical bud is from half to 

 three fourths of an inch from 

 the base of the season's stipe ; 

 later in the season, this bud will 

 have grown into an upright rudi- 

 mentary stipe which will de- 

 velop the following season, and 

 a new apical bud will have 

 formed at the end of a new 

 growth of the rhizome. It is 



FIG. 111. Pt.eris aquillna. A, a portion of the branching underground 

 stem or rhizome with fine roots ; B, a young leaf ; C, a mature leaf . (After 

 Sedgwick and Wilson.) 



