Function of the Septal Glands in Kniphofia . 1 5 
cellular spaces occur, and where the cells are generally 
slightly larger than those which are immediately hypo- 
dermal. 
(fi) The nuclei resemble those of the epidermis, but 
are smaller in proportion to the size of the cells. 
(y) The protoplasm is less dense, and the starch-grains 
more numerous than in the epidermal cells. 
Starch is present in the unmodified parenchyma of the 
septum, and occurs also in abundance in the central axis, 
where the grains are much larger. 
B. An older Bud (Fig. 5 ). 
(a) The epidermal cells are about the same size as the 
sub-epidermal cells, or only very slightly smaller. 
(a) The external wall is slightly convex, and has under- 
gone an increase in thickness ; in the largest buds it is 
seen to be differentiated into two layers, a very narrow 
external one which is sharply defined, and a broad in- 
ternal one, the inner outline of which is much less distinct 
than it was before the thickening took place ; in fact it 
has the appearance of having undergone corrosion. This 
thickening of the cell-wall is probably due to mucila- 
ginous degeneration of the inner layers, for the broad 
internal band no longer gives the reactions of cellulose, 
whereas the narrow ’ external band still appears to be 
coloured a pale violet by Schultze’s solution, though of 
this I could not be quite sure owing to its extreme thin- 
ness. This change never seems to involve the whole 
wall, since in older flowers, where the degeneration has 
reached its maximum, this thin membrane of unaltered 
cellulose can still be distinguished. 
(/3) The form and position of the nucleus are not 
appreciably altered. 
(y) The protoplasm is not so dense as in the cells of 
the younger bud, vacuoles being often apparent ; in still 
older buds however this vacuolation becomes less marked 
