. Text-book of botany, morphological and physiological. Botany. FIGS. 61-63.—Development oi tne stomata in the leaf of Hyacinthus orientates, seen in vertical section (X 800). which is narrower in the middle, wider without and within, and which connects the intercellular space / (the stoma) with the external air (Fig. 64). It is worth mention that before the division of the mother-cell an obvious cuticle has already over- spread it together with the adjoining epidermal cells. This cuticle is easily recognised in the condition B, Fig. 62, while still continuous; by the splitting of the partitio
. Text-book of botany, morphological and physiological. Botany. FIGS. 61-63.—Development oi tne stomata in the leaf of Hyacinthus orientates, seen in vertical section (X 800). which is narrower in the middle, wider without and within, and which connects the intercellular space / (the stoma) with the external air (Fig. 64). It is worth mention that before the division of the mother-cell an obvious cuticle has already over- spread it together with the adjoining epidermal cells. This cuticle is easily recognised in the condition B, Fig. 62, while still continuous; by the splitting of the partition-wall into two lamellae it finally becomes ruptured (Fig. 63), and by the circularising of the outermost layer of the now separated lamellae it is afterwards continued over the surfaces of the cleft (Fig. 64). If the process of the formation of the stoma is followed in a front view, it is seen that the splitting of the partition-wall does not extend throughout, but that a portion still remains undivided at each end where it adjoins the original mother-cell-well. The two cells which enclose the cleft, or Guard- cells, are not only distinguished from the other epidermal cells by this peculiar mode riu. o4. of division and of growth; they also differ from them in containing chlorophyll and starch. (2) In the family of Marchantieae belonging to the Hepaticae, the origin and structure of the stomata (Fig. 65, B, sp) is much more complicated; of this we must speak hereafter. Here it need only be pointed out that even before the formation of the stoma the epidermal cells become detached from those lying beneath over rhomboidal areas which are marked off from one another by walls formed of cells which are not detached (Fig. 65, J3, ss). These large hypodermal chambers, each of which opens to the outside in its middle by a stoma, are destined to enclose the chlorophyll-containing tissue of these plants. The layer of cells which forms the. 1 I was unable to detect nuclei immediately b
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Keywords: ., bookcentury1800, bookdecade1880, booksubjectbotany, bookyear1882
