HOOTS 



37 



The distinction between (i) and (c) is more evident when the 

 section has been exposed to the air for a few minutes and changed 

 somewhat in color. 



47. Structure and Contents of a Fleshy Root In some 



fleshy roots, such as the beet, the morphology of the parts 

 is rather puzzling, since they form many layers of tissue 

 in a single season, showing on the cross-section of the root 

 a series of layers 

 which look a little 

 like the annual 

 rings of trees. 



The structure of 

 the turnip, radish, 

 carrot, and parsnip 

 is simpler. 



Cut a parsnip 

 across a good deal 

 below the middle, and 

 stand the cut end in 

 eosin solution for 

 twenty-four hours. 



Then examine by 

 slicing off successive 

 portions from the 

 upper end. Sketch 

 some of the sections 

 thus made. Cut one 

 parsnip lengthwise 

 and sketch the section 

 obtained. In what portion of the root did the colored liquid rise 

 most readily? The ring of red marks the boundary between the 

 cortical portion and the central cylinder. To which does the main 

 hulk of the parsnip belong? Cut thin transverse sections from an 

 ink-stained parsnip and in those sections that show it, find out where 



Pig. 19. Much Magnified Cross-Section of a 

 very Young Dicotyledonous Root. 



h, root-hairs with adhering bits of sand; e, epi- 

 dermis ; s, thin-w.alled, nearly globular, cells of 

 bark; 6, hard bast; e, cambium; tr, wood-cells; 

 d, ducts. 



