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PRACTICAL BOTANY 



I. Those cut off from the sides of the apical cell 

 form the body of the root : these also divide by walls 

 in regular succession. Observe carefully the arrange- 

 ment of these walls, and by comparison of several 

 sections ascertain their order of succession, and their 

 relation to the various tissues of the root above 

 described. 



XV. Cut successive transverse sections of the apex 

 of a root which has been hardened in alcohol: this 



FIG. 15. Diagram illustrating the arrangement of cell-walls as seen in a median 

 longitudinal section throi:gh the apex of the root of a Fern. I. III. &c., in- 

 dicate segments cut oft' from the sides of the apical cell, which fro to form the 

 body of the root ; k, I, m, n, p, are successive segments from its base, which go 

 to form the root-cap. (After Goebel.) 



may easily be done if the root be held between pieces 

 of pith, or better by embedding in paraffin. If possible, 

 keep all the sections in their proper order of succession, 

 and mount in glycerine. Examine with a low power, 

 and choose out those in which the large apical cell is to 

 be seen. Observe carefully 



