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A TEXT-BOOK OF BOTANY. 



o 



FIG. 122. Development of schizogenous oleo-resin canals in Brauneria pallida. A, 

 intercellular space (o) between four parenchyma cells, being the seat of the early formation 

 of the canal and indicated by a yellowish oily content. B, intercellular oleo-resin canal 

 with five surrounding parenchymatous cells (p). C, later stage of canal showing separation 

 of small oily globules in the intercellular substance. D and E, the intercellular substance 

 showing an almost protoplasmic-like structure, some of the lining cells being developed as 

 papillae and suggesting that they might be in the nature of secretion cells, although it is 

 now considered that the oils and resins of this character are formed from a resinogenous 

 layer in the wall. F, longitudinal section showing the elongated secretory canal between 

 the rows of cortical parenchyma. 



