a2 ELEMENTS OF BOTANY. 
sections from the split surface and examine with the high power, with 
and without staining with iodine. 
Notice the appearance of the wood-cells and the ducts as seen in these 
sections, and compare with Fig. 41.1 
45. Structure of Fleshy Roots. if In some fleshy roots, such 
as the beet, the nature and relation 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, as 
shown in Fig. 40. | 
The structure of the turnip, radish, carrot, and parsnip is 
simpler. 
Cut a parsnip across a little below the middle, and stand the cut end 
in red ink for 24 hours. 
Then examine by slicing off successive portions from the upper end. 
Sketch some of the sections thus made. In what portion of the root did 
the colored liquid rise most readily ? Cut thin cross-sections of the ink- 
stained parsnip at several points along its length, and examine first with 
the low, then with a moderately high power of the microscope. The 
ring of red ink marks the boundary between bark and wood. Is the 
main bulk of the parsnip bark or wood? Is this ring marked by the 
presence of any particular kind of cell? Examine a longitudinal section 
to help you to answer the question. Cut thin transverse sections from 
an ink-stained parsnip and notice how the medullary rays run out into 
the bark. Stain one such section (from the slender portion of the root) 
with iodine, and sketch it as seen under a low power of the microscope. 
Where is the starch of this root mainly stored ? 
46. Use of the Nourishment stored in Fleshy Roots. —The 
parsnip, beet, carrot, and turnip are biennial plants ; that is, 
they produce seed during the second summer or fall after 
they are planted. 
The first season’s work consists mainly in producing the 
nourishment which is stored in the roots. To such storage is 
due their characteristic fleshy appearance. If this root is 
1The examination of the minute structure of the root is purposely made very 
hasty, since the detailed study of the structural elements can be made to better 
advantage in the stem. 
