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Transactions of the Royal Caxadian Institute 



ground. From this there arises a long clavate-cyHndrical internode 

 ending in a group of crowded short internodes, bearing a corresponding 

 number of small scale leaves. From this again spring usually three 

 long internodes, these likewise ending in a series of crowded internodes. 

 This is repeated till the finajl growth form is attained. From the crowded 

 internodes eventually arise the flov/ers in tight clusters. We may there- 

 for distinguish between short and long internodes— the latter being 

 finally long, cylindrical and naked, and especially adapted for my work 

 in view of the additional fact that they normally stand in all orienta- 

 tion^, roughly at an angle of ca. 60 degrees with the horizontal. 



Figure 2. Two pieces including growing terminal long internodes suitable for auxanometry. 



Slightly reduced. 



Structure of the Growing Internode. — The internode which serves for 

 the purposes of measurement is definitively a slender cylindrical shaft. 

 The cortex, covered by a cuticle which becomes strong with maturity, 

 is composed wholly of chlorenchyma. Stereome develops in the peri- 

 cycle and in the outer zone of the medulla, and the advent of this cir- 



