The natural history of plants, their forms, growth, reproduction, and distribution; . J If fir I /fv. Fig. 74. -Caryota propinqua. 312 PROTECTIVE ARRANGEMENTS ON THE EPIDERMIS. to the suns heat. One day, after a warm dry east wind had swept for only a shorttime over the foKage, it became quite brown, and in the evening all the leaves wereentirely dried up and dead. And yet leaf-segments of this palm appear to be firm,leathery, and dry, and one would have supposed them to be particularly well pro-tected against drying up. The section of part of a leaf which is represented infig. 75, however, co
The natural history of plants, their forms, growth, reproduction, and distribution; . J If fir I /fv. Fig. 74. -Caryota propinqua. 312 PROTECTIVE ARRANGEMENTS ON THE EPIDERMIS. to the suns heat. One day, after a warm dry east wind had swept for only a shorttime over the foKage, it became quite brown, and in the evening all the leaves wereentirely dried up and dead. And yet leaf-segments of this palm appear to be firm,leathery, and dry, and one would have supposed them to be particularly well pro-tected against drying up. The section of part of a leaf which is represented infig. 75, however, corrects this impression. This shows that the epidermal cells arecertainly very compact, by which the firmness of the leaf is materially increased,but that their walls are not thickened, being only like those of a delicate fern inthis respect. Under these small thin-walled epidermal cells lie large succulent cellswhich form the so-called aqueous tissue, the structure of whose walls likewisecannot limit evaporation; below these are the large succulent cells of the greentissue. A glance at this leaf
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Keywords: ., bookcentury1900, bookdecade1900, booksubjectbotany, bookyear1902
