r
part we will take specially the name given at present carelessly to a large
number of the plants themselves, 'flag.' This will give a more clear
meaning to the words 'rod' (virga), and 'staff' (baculus), when they occur
together, as in the 23rd Psalm; and remember the distinction is that a rod
bends like a switch, but a staff is stiff. I keep the well-known name
'blade' for grass-leaves in their fresh green state.

9. You felt, as you were bending down the paper into the form d, Fig. 21,
the difficulty and awkwardness of the transition from the tubular form of
the staff to the flat one of the flag. The mode in which this change is
effected is one of the most interesting features in plants, for you will
find presently that the leaf-stalk in ordinary leaves is only a means of
accomplishing the same change from round to flat. But you know I said just
now that some leaves were not flat, but set upright, edgeways. It is not a
common position in two-leaved trees; but if you can run out and look at an
arbor vitae, it may interest you {162} to see its hatchet-shaped vertically
crested cluster of leaves transforming themselves gradually downwards into
branches; and in one-leaved trees the vertically edged group is of great
importance.

[Illustration: FIG. 23.]

10. Cut out another piece of paper like a in Fig. 21, but now, instead of
merely giving it nicks at a, b, cut it into the shape A, Fig. 23. Roll the
lower part up as before, but instead of pulling the upper part down, pinch
its back at the dotted line, and bring the two points, a and b, forward, so
that they may touch each other. B shows the look of the thing half-done,
before the points a and b have quite met. Pinch them close, and stitch the
two edges neatly together, all the way from a to the point c; then roll and
tie up the lower part as before. You will find then that the back or spinal
line of the whole leaf is bent forward, as at B. Now go out to the garden
and gather the green leaf of a fleur-de-lys, and look at it and your piece
of disciplined paper together; and I fancy you will probably find out
several things for yourself that I want you to know.

11. You see, for one thing, at once, how _strong_ the fleur-de-lys leaf is,
and that it is just twice as strong as a blade of grass, for it is the
substance of the staff, with its sides flattened together, while the grass
blade is a staff cut {163} open and flattened out. And you see that as a
grass blade neces