70 
HOW PLANTS ARE PROPAGATED. 
171 
petals, eight stamens (twice four), and four pistils. So the flower of Trillium (Fig. 
1 62) is symmetrical ; for it consists of three sepals, three petals, six stamens (one 
before each sepal and one before each petal), and 
a pistil plainly composed of three put together, 
having three styles or stigmas. Flax affords an- 
other good illustration of symmetrical flowers (Fig. 
170) : it has a calyx of five sepals, a corolla of 
five petals, five stamens, and five styles. In such 
flowers, and in blossoms generally, the parts alter - 
nate with each other ; that is, the petals stand be- 
fore the intervals between the sepals, the stamens, 
when of the same number, before the intervals be- 
tween the petals, and so on. 
208. An Unsymmetrical Flower is one in which 
the different organs or 
sets do not match in 
the number of their 
parts. The flower of 
Anemony, Fig. 163, is 
unsymmetrical, having 
many more stamens 
and pistils than it has 
calyx-leaves. And the 
blossom of Larkspur 
(Fig. 171) is unsym- 
metrical, because, while p 
it has five sepals or 
leaves in the calyx, there are only four petals or co- 
rolla-leaves, but a great many stamens, and only one, 
two, or three pistils. The sepals and petals are dis- 
played separately in Fig. 172; the five pieces marked 
s are the sepals ; the four marked p are the petals. 
209. A Regular Flower is one in which the parts of each sort are all of the sar $ 
shape and size. The flowers in Flax (Fig. 170) and in all the examples prt 
ceding it are regular. While in Larkspur and Monkshood we have not only an 
unsymmetrical, but 
