288 THE MICROSCOPICAL NEWS. 
the starch less closely packed. Some grains will be met with that 
are not compound and exhibit but a single cross, others will be 
presented under different aspects, some showing the triradiate 
division of the granules, others a single diametral suture when 
the grain is seen from the side. Frequently the normal spherical 
form is departed from. Round the edges of the cells especially, 
the grains have, by mutual pressure, assumed the form of very short 
truncated cones with rounded angles. If the observer searches 
the cells carefully he will probably be rewarded by finding a 
few isolated granules, the appearance of which will of course vary 
according to their presentment, and these will afford a better idea 
of the true form of the granules than could possibly be obtained 
by any other means. Occasionally grains are met with having 
more than three component granules. 
The South American genus Smilax, from the roots of several 
species of which the sarsaparilla of the Pharmacopeeia is obtained, 
belongs to the natural order Smilacez, which together with a few 
other orders, presents a remarkable departure from the normal 
type of monocotyledons. The form of the embryo and of the 
flower, the minute structure of the zrial stem and its branches, 
and the general character of the plant are exactly those of other 
monocotyledons, but the veins in the leaves form a network and 
the viizome or creeping underground stem has its woody tissue 
disposed in a ring round a central pith or medudla, and is surrounded 
in turn by a parenchymatous cortical layer. These characters are 
as distinctly dicotyledonous as those before mentioned are mono- 
cotyledonous.* ‘The arrangement of the bast and xylem in the 
root is somewhat different, for instead of each bundle consisting of 
an internal woody portion separated by a cambium ring from an 
external bast portion the two constituents are arranged collaterally, 
large xylem bundles consisting of large vessels and thick-walled 
prosenchymatous cells alternating with much smaller bast bundles 
composed in the main of sieve tubes, the whole being surrounded 
by a single layer of very thick-walled cells, representing the vascular 
bundle sheath. Under a 1 inch objective this arrangement will be 
well seen in the accompanying preparation, and a } inch applied 
to the sieve tubes will show here and there the perforated end 
walls or sieve plates between the ends of adjacent vessels. All the 
elements of the root are highly lignified, and polarise strongly with- 
out the aid of a selenite. 
* Contrast this with the trans. sect. of the Bulrush, which is an ordinary 
monocotyledon. 
