122 W or sdell. — On the Comparative Anatomy of 
through one of these shows four or five leaves arching right 
over a broad, flat apex of small, often purplish, cells. 
The stem may attain a length of 6-8 inches, and bear 
several flowers at its summit. It has usually a very much 
bent and curved attachment to the root, owing, probably, to 
the fact of its having originated laterally on that organ, and 
been forced to bend upward towards the daylight. In its 
middle portion, about half-way between its attachment to the 
root and the inflorescence, it sometimes becomes considerably 
thickened and swollen, tapering off again towards the apex. 
Anatomy of the Stem. 
In a transverse section of an adult stem are seen a number 
of bundles scattered irregularly throughout the ground-tissue ; 
they vary in number and in size. So reduced and modified is 
the stem of this species, that not only are the bundles 
irregularly distributed, but the orientation of each separate 
bundle is no longer normal ; the xylem is usually in the 
centre, surrounded entirely by phloem ; the elements com- 
posing the bundle are very scattered ; there is a considerable 
amount of parenchymatous tissue present. 
No endodermis could be distinguished in this stem. 
The cells of the ground-tissue are exceedingly loosely 
arranged and much rounded off; they are large in contour 
and contain much starch. More will be said of these elements 
in treating of the longitudinal section. 
No stomata were observed anywhere on the stem, either in 
transverse, longitudinal, or surface section. 
In some stems stone-cells appear to be entirely absent ; in 
others they are present, surrounding the bundles or in the 
ground-tissue ; but they are not nearly so well-developed as 
those of the root, being much thinner-walled. 
If successive transverse sections are made in the lower part 
of the stem, near its junction with the root, it will be seen that 
the bundles become fewer in number and larger, owing to 
fusion one with another, and also that they arrange themselves 
