CHAPTER IV. 

 BUDS AND STEMS. 



PROVIDING MATERIALS. 



Most of the material required in the study of buds and stems can be 

 procured out of doors at any time before growth begins in the spring. 

 If the study is to be taken up later in the season, twigs of horse chest- 

 nut, Cottonwood, and lilac with winter buds should be secured and kept 

 in 2% formalin until needed. In those schools where the study of 

 botany is begun immediately after the Christmas vacation, strong 

 shoots of the above plants should be cut off and placed in jars of water 

 at the beginning of the term, and kept in a warm place, in order that 

 their buds may be unfolded by the time the study of buds in their win- 

 ter condition has been completed. The twi^s may be crowded into the 

 jars quite closely, and there should be several twigs of each kind for 

 every student. The water in the jars should be frequently changed. 



If Aristolochia is not at hand, it can be obtained of dealers in botani- 

 cal supplies.^ Branches of Tilia (linden) can be used to good advan- 

 tage for sectioning if Aristolochia cannot be obtained, and branches of 

 elm might be used, although less advantageously. Aristolochia, how- 

 ever, is the best for this study. These branches and small stems of 

 Indian corn should be taken during the growing season and placed for a 

 week or so in 70% alcohol, and then kept in equal parts of alcohol, 

 glycerine, and water until needed. This method of treatment makes it 

 easier to cut good sections. 



OBSERVATIONS. 



53. Make drawings of a twig of horse chestnut in its 

 winter condition, showing the relative size and position of 

 all exterior structures. Where did last year's leaves grow 

 on the twig .' 



1 Cambridge Botanical Supply Co., Cambridge, Mass. 

 45 



