74 
BOTANICAL INDEX. 
of farinaceous and saccharine matter, well calculated to feed a luxuriant growth of 
foliage, especially in early Spring; and, also, to induce new buds or shoots to 
break out at the side of the old rhizome, and form a large clump or cluster, hut 
which, in time, separates into distinct plants. These, like the stock of a hardy 
shrub, remain dormant through the Winter, or, iii the language of botany, are per- 
ennial, and are usually seen in short, knotty sections, representing its period of 
growth, as seen in Fig. 149, from Gray’s Lessons in Botany, and for which we are 
indebted to his kindness for the use of the cut to illustrate this article. The new 
growth takes place each year from near the growing end of the rhizome, while a 
corresponding portion decays from the old growth' of former years, thus keeping a 
mature plant at about the same length, but by its branching out at the side of the 
rliizoma, in a short time a large clump is formed. Usually the growing end of last 
year was so immature and unripe when winter set in, that it had decayed to such an 
extent that the new growth must break out from a healthy and sound portion as 
near the end of the root as possible. Let us look again at the prostrate trunk or 
stock of the plant, to satisfy ourselves it is not a root in the true meaning of the 
word. Here we find a perfectly formed bud at the end of the stock, as all monoco- 
tyletllea or endogenous buds are produced, i. e., growing or unfolding from the end, 
and true leaves joined directly on the stock, and closely overlapping each other; so 
closely together do they stand, that when they have decayed each year, the rliizoma 
presents a series of scars or rings with some of the undecayed fibrous nerves of the 
leaves still attached, to mark the successive position of the leaves; all of which show 
us plainly enough that they are not roots, but prostrate forms of stems. — Gray. 
The leaves are also very little understood, except by botanists, for in place of one 
surface facing up (towards the sky) and the other down (towards the ground) as is 
usual, or one surface facing the right and the other the left, as in some cf the Aca- 
cias, etc., in the Iris, the leaf is linear or sword shaped, and erect; but “each leaf is 
formed and folded together lengthwise, so that what would be the upper surface is 
within, and all grown together except next the bottom, where each leaf covers the 
next younger one. It was from their stradling over each other, like a man on horse- 
back, that Linnams, with his lively fancy, called these equitant leaves.” — Gray's 
Lessons. 
But if the stems and leaves are curious and little understood, what shall we say 
of the flowers. They are erect, usually from a spatliaceous bract of two or more 
leaves, produced, usually, singly in succession, each one opening hut once, convolute 
in the bud in two sets, with no true calyx, but a corolla-like perinth, the tube pro- 
longed beyond, and adhering to, the three-celled ovary, while the perinth appears 
to grow upon its summit; the perinth consisting of six nearly equal alternating 
parts, the three outer divisions refiexed or bent back with usuallj' a bearded crest, 
(Fig. 146-&), the three inner ones usually smaller, erect or incurved, and bent to- 
wards a common centre. Stamens three, alternating with the three inner divisions, 
but opposite the three outer divisions of the perinth, with their linear and oblong 
anthers fixed at the base, and facing out towards the perinth and open on that side; 
Figs. 14G-e and 147 show the anthers in position, the perinth-limbs being removed at 
a and b. The style (pistil) is short and single, nearly connate (united or grown to- 
gether) with the tube of the perinth, while the three petal-like divisions or stigmas 
(Fig. 146. cl) are distinct; opposite the three cells of the ovaries, refiexed and stand- 
ing directly back of, and closely overhanging, the three stamens. The end of the 
stigma is notched and under this notch, on the lower face of the petal-like 
branch of the style is the real stigma, in the form of a thin shelf or short 
lip, which is stigmatic only on its inner surface. The peculiar structure of the 
flower of the Iris, together with the curious provisions for fertilizing the same, can- 
not be more clearly and instructively described, than has already heen done by Prof. 
Gray in his entertaining little book, entitled, “ How Plants Behave," which, by the 
way, is one of the choicest literary gems in the English language, and should be in 
the possession of every plant lover, whether they study it as an instructor in botany, 
or simply grow plants and flowers for their beauty. The following extract from the 
chapter on “how plants employ insects to work for them” says : — “We notice that 
the stigma is higher than the anthers ; but that is only a part of the difficulty. The 
anther and stigma face away from each other. The anther faces outward, and dis- 
charges its pollen through two long slits on the outer side only. The thin plate or 
shelf is stigma only on its upper or inner face which is roughened and moistened 
in the usual way for receiving the pollen ; the face turned towards the anther can- 
not receive the pollen at all.’ 
It is easy to see from the above description of the construction of the flower, that 
it cannot by any possible means become fertilized, except by the aid of insects, and 
then can only he accomplished under the following conditions: — “When bees, for 
instance: visit the Iris flower, they alight upon the outer and recurved, usually cres- 
