November 2, 1972.] THE PHARMACEUTICAL JOURNAL AND TRANSACTIONS. 
341 
THE MICROSCOPE IN PHARMACY. 
BY HENRY ROCKLINGTON. 
('Continued from p. 302.) 
Sars.e Radix. —The structure of sarsaparilla root 
differs widely from that of the roots I have hitherto 
discussed in these papers, where I have dealt chiefly 
either with roots of true exogens, where the cha¬ 
racteristic concentric rings are found disposed 
round a central medulla (sometimes suppressed), 
and medullary rays proceeding therefrom ; or with 
tubers, conns and the like, of herbaceous endogens, 
not possessing any true stem structure at all. But 
we now have to do with a class of structure which is 
essentially different from those other structures, and 
also with a structure which is on the face of it 
transitional, and unites the features of the other two. 
The structure of the aerial stem of Smilax is very 
different from that of the roots and rootlets, and is 
that (with slight modifications) common to all 
arborescent endogens. The structure of the root on 
the other hand, is approximated to that of the 
aberrant exogens lately mentioned. The chump 
or rhizoma unites the two classes of structure. 
In the aerial stem there is no medulla, there are no 
regular wood-wedges, or concentric rings, and no 
medullary rays. There is no true bark or separable 
rind. Whence it follows that the course I laid 
down early in the present series for the examination 
of roots and stems, must be supplemented. 
In investigating the structure of fully developed 
endogenous stems (such as those of palms, bamboos, 
etc.) we shall find it of primary importance to dissect 
them longitudinally for some considerable distance, 
that the course of the vascular bundles may be fol¬ 
lowed as far as possible throughout. In palms, if a 
“vascular bundle be traced from the point of the 
insertion of the leaf backward, it is found that it 
runs in a curve, the convexity upward, to the centre 
of the stem; then, in the neighbourhood of the centre 
runs down a certain extent deep in the stem, but 
soon again loses the direction parallel to the axis of 
the stem, gradually again approaching the surface 
till it lies beneath the rind, and there passes down 
the stem beneath it.”* 
All monocotyledons do not possess identically this 
same structure. Aloes is a notable instance of 
variation therefrom, as also the several members 
of the sub-class Dictyogeme (Lind), of which Smilax 
and the easily procured Tamils communis are 
members. In Smilax, according to Henfrey, the 
bundles do not pass wholly into the leaves, as in 
palms, but run continuously through the structure. 
Henfrey also states, erroneously as regards some 
species at least, that the bundles stand in circles. 
In other respects, the stem structure of Smilax is 
endogenous, and examinations of its root and 
stem must severally partake of the plan recom¬ 
mended in the examination of exogenous stems, and 
that more applicable to endogenous. 
I will take the stems first, as they will not occupy 
us long, inasmuch as they are not officinal, and it 
has unfortunately happened that I have not had 
opportunities of examining any large number of 
species, and none in a fresh state. It may be as 
well to remark here that slides of sarsaparilla, as 
sold by English dealers, are very commonly pre¬ 
pared from the aerial stem, and not from the root. 
* Mold, * On the Structure of the Palm Stem.’— Ray 
Society’s Publications. 
Third Series, No. 123. 
My attention was first called to the structure of 
pharmaceutical botanicals by a “ mounter’s slide ” of 
8. syphilitica given me years since by a west 
country friend, and found on examination to differ 
so widely from the usual diagnosis given in botanical 
books that I commenced an examination of the 
species. I then prepared one of our British Tamus, 
and presently concluded that the slide should go 
with my illustrations of stem, and not of root struc¬ 
ture. I mention this lest beginners should be simi¬ 
larly troubled. 
I select the stem of Mexican Sarsaparilla for 
description. The general appearance in cross section 
is that of a cane or bamboo. The vascular bundles 
are large and evenly distributed through the stem. 
In longitudinal section some are seen to proceed from 
leaf scars, but they run straight and are continuous 
down the stem as soon as they have assumed a direct 
course. Three classes of structure enter into the 
composition of the vascular bundles. First, large 
pitted vessels with oblong pits. Second, long, thin, 
walled cells. Third, liber or wood cells. The wood 
cells are of uniform size, but vary in shape, as seen 
in cross section, and are very porous. Their length 
is variable, and often considerable; their diameter 
about the 1 -1000th of an inch. The vascular bundles 
are more or less circular in cross section, and stain 
intensely with magenta. A cross section judiciously 
stained and mounted in balsam forms a pretty object 
but is not equal to a similar section from the root. 
The vessels are septate, the septa (sometimes ab¬ 
sorbed) are porous. The pitting is various, usually 
oblong as above stated; it is sometimes in the 
smaller vessels punctate. Some of the vessels have 
scalariform markings. The cellular tissue consists 
of subcylindrical cells containing great quantities of 
starch in compound granules (two to six) and with an 
indistinct punctate or radiate liilum. Special cells, 
apparently not porous, contain bundles of acicular 
raphides, such as are commonly found in this and 
some other natural orders. 
The structure of the rind need not occupy us now. 
The connection of the vascular vessels of the stem 
with the root is not easily made out. In fact, it is 
a matter of very great difficulty when we have to 
deal with dried specimens only, and it is further com¬ 
plicated in sarsaparilla by the confused structure of 
the “chump.” We shall better understand it if we 
dissect the root upward towards the chump, where 
we shall find that the vessels which surround the 
central cellular portion gradually spread out and 
apparently lose themselves amongst the vessels of the 
rhizoma, but may be traced with care into the stem. 
The central cellular portion of the root is lost sight of 
immediately we enter upon the rhizoma, but probably, 
as Molil has shown is the case in the palm stem, it 
“penetrates the fibrous layers of the stein and 
spreads out on the outer layers of wood bundles. * 
The structure of the stems of such other Smilacetp 
as I have been able to examine, do not differ from 
the foregoing so greatly as to render their description 
desirable in this place, and I will in my next paper 
proceed to discuss the structure of the roots ot the 
more common commercial varieties, and to describe 
as well as possible without woodcuts their dis¬ 
tinguishing structural peculiarities. 
* Mold adds, “ in the form of a disk ” but I have not 
been able to satisfy myself of this in the case ot sarsaparilla. 
One tuberous chump appears to point in this direction. 
