124 
Notes. 
nula rapunculoides the median vein forks before reaching the apex ; 
the two branches of the fork form the sides, and the slightly concave 
apex the base, of a triangular patch. Water-pores occur among the 
epidermal cells on the upper surface of this patch, and resemble 
ordinary stomata, except that they are smaller. The epidermal cells 
of this patch are also smaller and less wavy in outline than the other 
epidermal cells of the plant. No pores or stomata occur anywhere else 
on the upper epidermis. 
On the under surface of the cotyledon the arrangement is the 
opposite of that on the upper : the whole surface, except the triangular 
apical patch, is well supplied with stomata ; the cells of the triangular 
patch are small and rectangular, but have neither pores nor stomata. 
The epidermal cells under the median vein are long and rectangular, 
and have no stomata. 
Under the triangular patch of cells the median vein anastomoses 
with two lateral secondary veins which previously branch off from the 
median ; these veins lose their spiral vessels and the prosenchyma 
alone forms a broad epithem which 
occupies the space under the triangular 
patch. 
The cotyledons of Campanula rotundi- 
folia , C. pyramidalis, and C. persicifolia 
resemble those of C. rapunculoides . 
C. rotundifolia (Fig. i b) has fewer 
water-pores — only three or four — but 
in addition it has six or seven stomata 
among the epidermal cells of the upper 
surface. The whole of the under surface 
is supplied with normal stomata, and 
the apex differs from the rest of the 
under surface only in having smaller 
cells. 
The upper surface of the cotyledons 
of C. pyramidalis resembles that of C. 
rapunculoides ; the under surface that 
of C. rotundifolia. 
The cotyledons of C. persicifolia 
resemble those of C. rapunculoides , but the water-pores are only six or 
seven in number. 
Fig. i b. Campanula rotundi- 
folia. Group of three water-pores 
at apex on upper surface of coty- 
ledon. The median vein of spiral 
vessels terminates in prosenchyma 
under the pores. Six or seven 
ordinary stomata occur on the rest 
of the surface. 
