534 



BOTANY OF CROP PLANTS 



In a cross-section the of "carrot" the following tissues 

 may be seen, from the outside to inside: (i) periderm (skin); 

 (2) cortex and phloem; (3) cambium; (4) central region 

 (wood and pith) . A good carrot is one with a proportion- 

 ately large cortex and phloem, because in these most of the 



sugar is stored. During 

 the second season of 

 growth, a rough, hispid 

 stem, 2 or 3 feet high, and 

 with spreading branches 

 is sent up from the 

 "crown" of the carrot. 



Leaves. — All the leaves 

 are decompound (doubly 

 compound). The lower 

 ones are two- to three- 

 pinnate, the segments 

 linear or lanceolate, den- 

 tate, lobed or pinnatifid, 

 the upper ones smaller and 

 less divided. 



Inflorescence and 

 Flowers. — The inflores- 

 cence is a compound 

 umbel. At maturity, the 

 outermost pedicels bend 

 inward, the whole forming a structure resembling a bird's nest. 

 The involucral bracts are long, and cleft into a number of 

 narrow lobes. The involucels, at the bases of the umbellets, 

 are made up of entire or toothed lobes. The flowers are 

 small and white, the central one of each umbel often purple, 

 or all the flowers are pinkish. The calyx teeth are lacking. 

 There are five petals, obovate, and with the tips turned in. 



Fig. 219. — Fruit of carrot (Daucus 

 carota). A, cross-section; B, external 

 view. {A, after Sargent). B X lo. 



