Jan. 1907] PECULIARITY IN PITH OF CUCURBIT. 247 
in the centre, and phloem on the outside and also on the 
inside. 
In one part of the stem certain ceils form a projection 
into the central cavity. This projection appears to have 
originated as a single cell, and afterwards in the centre of 
it there is meristematic tissue. As this structure is followed 
along the stem, it increases in size till it gradually fills up 
the whole of the central cavity. But before it has altogether 
done so, in the centre of the projecting portion—that is to 
say, in the centre of the meristematic tissue—another cavity 
arises which differs entirely in appearance from the original 
central hollow. It is bounded by a very regular layer of 
cells, which have thicker walls than the other cells of 
the stem, and have abundant cell content. Two or three 
rows of cells next to this layer also differ from the others. 
From the surrounding layer of cells there project outwards 
into the cavity hairs of two kinds, pluricellular and glandular. 
The former are the more numerous, and are of the kind 
described by De Bary as conical multicellular hairs.1 The 
foot cell differs slightly in appearance from the others. 
There may be as many as seven or eight cells ina hair. All 
the cells are full of protoplasm. 
The glandular hairs are not nearly so numerous. They 
are similar to those which De Bary calls capitate glandular 
hairs,! z.e. the free end is swollen to form a round head, the 
transverse section of which exceeds that of the stalk. The 
stalk is short, 1—3 celled. 
The outside of the stem is also covered with hairs, both 
pluricellular and glandular, and these are absolutely identical 
in appearance with the hairs which fill the cavity. 
The cells surrounding the cavity are exactly like the cells 
of the epidermis. 
These facts point to the conclusion that we have here an 
internal epidermal structure. It is not exactly the case, 
however, that the cells surrounding the central hollow, in 
response to an air environment, have started to produce an 
epidermis with hairs. Such would doubtless be a likely and 
natural explanation if it were not for the way in which the 
hair cavity arises. 
1 See De Bary, ‘“‘ Comparative Anatomy of Phanerogams and Ferns,” 
p. 59. 
