98 



PEACTICAL BOTANY 



some are much larger than others. The large scars mark 



seasons when the fruit matured, and much smaller ones show 



that it dropped before it was full grown. 



Do fruits generally mature on any given 



fruit spur two years in succession?^ 



88. Structure of leaf buds. Scaly win- 

 ter leaf buds consist, as shown in Figs. 78 



Fkj. 82. Twig of cotton- 

 wood with buds in winter 

 condition 



b.sc, bud-scale scars. Two 

 thirds natural size 



Fig. 83. Cottonwood twigs, April 15 



The flower buds (dpyeloping iuto catkins) 



are fully open, but the leaf buds are still 



closed. Kc'luced 



and 79, of in) one or more outer layev.s of srak's; (J) rudimen- 

 tary leaves ; (c) a central axis, at tlic tip of which is the (/roirhi;/ 

 point (Fig. 36), a region of cells capable of rapid sub-division, 

 by means of which the elongation of the shoot is produced. 



1 Spc Bailey, Lessons with Plants, Part I. The MacniiUan Company, 

 New York. 



