Structure, etc., of Epiphegus Virgintana. 369 
Stomata are frequently present along the stem epidermis. 
They show a very simple structure; there are two short 
swollen guard cells, with a slight orifice between. The entire 
stoma projects out considerably beyond the level of the 
stem surface. Similar simple stomata are abundant through- 
out the plant, being found on stem, bracts, on the corolla, 
even on the style, a quite rare occurrence in plants. This 
abundance of stomata is a usual accompaniment of para- 
sitism. The parasite takes in an enormous quantity of sap 
from the host, as is evidenced by the rich deposit of starch 
through all its tissues. So a great excess of water must be 
brought into the plant, and a plentiful development of sto- 
mata is needed in order to transpire off this excess. Since 
leaves are present only in a rudimentary state, other organs 
are compelled to assist in producing these stomatic struc- 
tures. 
A noticeable fact in this connection is the rapidity with 
which the plant withers after being severed from its connec- 
tion with the beech root. This is no doubt due to the exces- 
sive transpiration caused by the numerous stomata. 
The stem epidermis consists of a single row of narrow 
cubical cells. A brown thickening is developed, especially 
on the outer wall, but to some extent on the other walls. The 
cortex cells are large and spherical, and are frequently sep- 
arated by considerable spaces. Sometimes fine strands are 
seen connecting two cell walls, across such intervening 
spaces. The cells of the outer cortex are devoid of starch, 
but starch is abundantly present in the deep layers of the 
cortex and in the central pith region. Some starch grains 
are simple spheres, others are of a complex structure, con- 
sisting of a number of spherical segments fitting together. 
The bundles lie in a ring around the pith. Between them 
rays of the pith pass out to join the outer cortex, completely 
isolating each bundle, and so giving to the stem an aspect 
that is much looser and more primitive than that of the 
typical dicotyledonous stem. This state of affairs is prob- 
