ON HELLEBORUS NIGER. 
229 
Helleborus fcetidus.—li is not easy to mistake the root of this 
plant for that of Helleborus niger. It is thick, woody, much- 
branched, and of a chestnut-brown color. Upon examination of 
an oblique section of the fresh root, of the thickness of the 
finger, a light-green pith cylinder may be observed, blending, as 
it were, with the cortical portion ; if the root be dried, this en- 
tirely disappears. The radicles have a ligneous fracture, and 
internally, a yellowish color. 
With the aid of the microscope the difference between these 
roots may also be demonstrated. It is necessary, however, in 
connection with other observations, to study sections of the radi- 
cles ; for this purpose the smaller are to be preferred. M. Wal- 
pers thus describes the microscopic structure : 
An oblique section of the radicles of Helleborus niger, shows 
a thick cortical portion, surrounded by a stratum of semi-cylin- 
dric, rather thick-walled epidermis cells, dark brown only on 
their external wall. The cortical layer consists of large, tolerably 
compact, 5 — 6 sided parenchyma cells, which are closely filled 
with minute, spherical, conglomerate fecula granules. The 
medullary body is irregular, sharply 4 — 5 cornered, and consists 
of very thick-walled, reticulately punctate vessels. Between the 
projecting rays of the medulla is a collection of thin- walled elon- 
gate cells, filled with fecula granules and oil globules. In several 
places the bundle of vessels of the medullary portion is invaded 
by pith-cells similar in form to those of the cortex, and like them 
filled with fecula. 
Helleborus viridis differs, inasmuch as the cortical layer of its 
radicles contains but few fecula granules, and many oil globules. 
The central portion is compact ; the vessels are reticulated in 
the same manner, but are never invaded by pith-cells ; there are, 
indeed, but few pith-cells visible. 
Very much the same structure may be remarked in the radi- 
cles of Adonis vernalis ; the epidermis-cells, however, are not 
only brown on their external, but also on their internal walls. 
The cells of the cortical and medullary layers contain minute 
spherical, but not conglomerate fecula granules, together with 
numerous oil-globules. The central portion, consisting of dotted 
vessels, is sharply 4 — 5 cornered, either compact, like that of 
Helleborus viridis, or divided by 4 — 5 rayed pithy bodies into 
as many star-formed and separate fascicles of vessels. 
