28 i 
Seedlings of Zea Mais and Phoenix dactylifera. 
have lost most of the granules which they contained in the previous stage. 
Those which remain are small and quite evenly distributed in the parietal 
layer of cytoplasm. The nucleus is smaller than in previous cases. It is 
situated near the centre of the cell, and connected to the lateral walls of 
cytoplasm by radiating strands. The deeper-lying layers of cells are nearly 
empty of granular material at this time. The elements of a fibro-vascular 
system are beginning to appear among the hypodermal cells. 
Observations upon seedlings twenty-nine days old. The parts of the 
embryos outside the seed average 4 cm. in length. The cells and cell- 
contents are much the same as in the last stage, except that they are more 
depleted of granular material. The granules which yet remain are nearly 
all confined to the epidermal and first hypodermal layers. 
Observations upon seedlings thirty-three days old. The scanty granular 
material which yet remains in the cells of the absorbing organ exists in the 
form of large granules. Each epidermal cell contains a large vacuole 
surrounded by a thin layer of cytoplasm. The nuclei of these cells are 
smaller than in previous stages. 
Observations upon seedlings fifty days old. The cells of the absorbing 
organ, both epidermal and hypodermal, are empty of granules, so far as can 
be ascertained by staining with iodine or methylene blue. The cytoplasmic 
body and nucleus retain the same size and relative position as in the previous 
stage. 
B. Studies of Microtome Sections. 
The morphology of cells in seedlings six days old (Fig. 9). There are 
very few changes from the condition which has been described for the resting 
stage in the living material. The epidermal cells of the absorbing organ 
show no elongation as yet. The cytoplasm contains a large amount of fine 
granular material which may represent the zymogen, because it disappears 
as enzymes are formed. The spherical nuclei, whose average diameter is 
about two-thirds the width of the cell, are usually situated near the centre 
of the cell. When stained with Kleinenberg’s Haematoxylin, the chromatin 
is demonstrated as very small grains on the nodes of the linin network at 
the surface of the nucleus. The karyolymph does not contain granular 
matter as in the case of Zea. A small nucleolus is present in each nucleus. 
The morphology of cells in seedlings nine days old. The cells show 
certain well-marked changes from the conditions described in the preceding 
stage. The zymogen granules in the cytoplasm have not only increased 
in size, but in their affinity for stain. All the cells of the embryo are 
filled with proteid granules which stain more cyanophil than at any 
subsequent time. The densest accumulation of granules is in the hypo- 
dermal layers of cells. There is also a larger amount of chromatin present 
in the nucleus, the difference being due to an increase in the size of the 
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