CHENOPODIACE^ 



305 



the center; new rings of growth are placed upon these, while 

 the new leaves come from the center of the crown. Hence, 

 there is a crossing of the older and younger bundles that lead 

 into the leaves. 



Rings of Growth. — The rings of growth vary in number, de- 

 pending upon the length of the growing season. Ordinarily, 

 six to ten rings complete their growth. The cambium rings 

 arise in the pericycle, each remaining active but for a short 

 period of several weeks. 



Leaves. — A cluster of large leaves is developed from the 

 crown of the beet during the first season. The oldest leaves 



Fig. 123. 



-Beet (Beta vulgaris). A, floral diagram; B, flower, face view. 

 (A after Bessey.) 



are on the outside, the youngest toward the center. Each 

 leaf has a long petiole which broadens out at the base; the 

 blade is large and roughly triangular in shape at the base, and 

 longer than broad; the veins are prominent. 



Inflorescence. — The inflorescences are loosely spicate and 

 terminal. The flowers are arranged along an axis, singly or 

 in dense, sessile clusters, each of which is subtended by a small 

 bract. Fig. 122, A shows a characteristic cluster of beet 

 flowers in the axis of a bract. 



Flowers. — Beet flowers are perfect. The perianth consists 



