Of Aphylion Uniflorum, Gray. 113 
is not uniformly present, and some of the cortical cells show 
it also. I have found no trace of a symbiotic fungus in the 
epidermis. 
Beneath the epidermis is the cortex, some ten or twelve 
cells deep. These cells contain many small, rounded starch 
grains, which are usually placed on the lower and inner sides 
of the cell. Chatin states that the epidermis contains fine 
granules, and the parenchyma large granules, “ni verts ni 
amylaceés,”’ but Koch states that starch is invariably present in 
the roots of Orobanche. Chatin may possibly have reference 
to the oil-like globules mentioned above. 
Within the cortex is a reduced and degenerate bundle-sys- 
tem. The bundle-sheath is quite absent in some roots, in 
others it is represented in patches. The arrangement of wood 
and bast varies considerably. It is most commonly diarch. 
A modification of this is found, in which the wood projects 
on one side of the bundle, so that the phloem of that side is 
subdivided. A smaller proportion show a triarch arrange- 
ment, while in some there seems to be an indiscriminate dis- 
tribution of wood elements. The xylem consists of rather 
short, pitted-reticulate elements, and though less in bulk than 
the phloem, is better differentiated. The phloemis composed 
of elongated elements, filled with highly granular contents, in 
which nuclei frequently persist. Sieve-tubes seem to be 
entirely absent. Protoplasmic connections between the cells 
corresponding functionally in all probability to similar pro- 
cesses in sieve-tubes were sometimes observed. 
Root-hairs are either entirely absent, or are doubtfully rep- 
resented by a few small, widely scattered, dermal papille. 
Absorption must therefore be impossible for these roots. This 
is in harmony with Koch’s statement as to the total absence 
of root-hairs in Ovrobanche speciosa, O. minor, O. ramosa, 
and O. Hedere, which he studied embryologically. Koch 
finds a root-cap on the soil-roots, 7 ¢. the secondary 
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