. Plant studies; an elementary botany. Botany. i2 PLANT STUDIES but it usually occurs, and does not necessarily imply ex- treme conditions of any kind. However, if the cells of the palisade tissue are unusually narrow and elongated, or '"y^. Fig. 32. Section through a jicjrtion of the leaf of the ye\S' (Tunis), showing cuticle (ci, epidermis (t), ami the u]i])er portifin of the palisade cells (p). form two or three layers,, we might infer the probability of exposure to intense light or drought. The accompanying illustration (Fig. 31) shows in a striking way the efEect of light intensity u
. Plant studies; an elementary botany. Botany. i2 PLANT STUDIES but it usually occurs, and does not necessarily imply ex- treme conditions of any kind. However, if the cells of the palisade tissue are unusually narrow and elongated, or '"y^. Fig. 32. Section through a jicjrtion of the leaf of the ye\S' (Tunis), showing cuticle (ci, epidermis (t), ami the u]i])er portifin of the palisade cells (p). form two or three layers,, we might infer the probability of exposure to intense light or drought. The accompanying illustration (Fig. 31) shows in a striking way the efEect of light intensity upon the structure of the mesophyll, by contrasting leaves of the same jilant exposed to the extreme conditions of light and shade. The most usual structurtil adaptations, however, are connected with the ejiidermis. The outer walls of the epi- dermal cells may become thickened, sometimes excessively so; the other epidermal walls may also become more or less thickened; or even what seems to 1)0 more than one epi- dermal layer is found protecting the meso- phyll. If the outer walls of the eiiidermal cells Continue to thicken, the outer re- gion of the thick wtill loses its structure and forms the cuticle, which is one of the. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original Coulter, John Merle, 1851-1928. New York, D. Appleton and Company
Size: 2787px × 897px
Photo credit: © The Book Worm / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1900, bookdecade1900, booksubjectbotany, bookyear1900
