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nuclei, deeply stained granular cell contents, and well marked cell 
walls; 2) numerous sense cells, brought out only by the Gorcı stain; 
3) gland cells, increasing in number from few at the tip to many in 
the anterior part of the growing zone; and 4) basal, or reserve cells, 
the fundaments of the gland cells. At, and near the extremity at 
least two-thirds of the cell layer is made up of the deeply stained 
columnar cells; there being present also basal cells, a few gland cells, 
and many sense cells. The columnar cells lose their predominance 
towards the anterior part of the growing region because of the many 
gland cells developing in this portion. From the pressure of these 
glands, the columnar cells lose their regular outline, becoming the 
supporting cells of the fully differentiated epidermis. The basal cells 
form an incomplete layer beneath the other cells of the epidermis in 
the growing zone. They are most numerous near the tip, become 
scattering in the anterior portion, and finally disappear near the 
anterior limit of the growing zone, having developed into the gland 
cells. They are small, irregular, flattened cells with poorly defined 
walls, containing a small amount of feebly staining cytoplasm, and a 
medium sized, or large, oval, lightly stained nucleus (Fig. 1, No. 1 
and 2)'), 
Glands. 
The epidermal glands develop from the basal cells throughout the 
growing zone (Fig. 1, No. 1), the change taking place largely in the 
anterior part of this region. In successive stages of the gland formation 
one of these basal cells becomes broader (Fig. 1, No. 2), and, by 
means of a bluntly pointed process, pushes its way between the other 
cells towards the cuticle. In the completely formed gland, this process 
has reached the cuticle and broadened out somewhat against it (Fig. 1, 
No. 3). The newly formed gland is the largest cell of the epidermis, 
10 u to 16 w in transverse diameter, and in height the thickness of 
the epidermis, 8 « to 10. It is thin-walled, in some cases irregular 
in outline. The nucleus is usually one-fourth to one-third the vertical 
diameter of the cell; and is situated, as a rule, in the lower one-half 
of the cell. It takes a light haematoxylin stain, and shows a well 
marked reticulum with one to several nucleoli. The cell contents, 
nearly unstained, show small granules gathered into rounded masses 
in all parts of the cell. A pore canal, leading from the cell thro the 
1) All drawings made with camera outline, and subsequently 
enlarged when neccessary. Zeiß, Apochromatic 2 mm Objective with 
Ocular 4 or 8 was used in all cases. 
de 
