said to be _multiple_. The Pumpkin is an example of this. The root of
the Pea is described in the older editions of Gray's Lessons as being
multiple, but it is generally simple. Indian Corn, also, usually starts
with a single root, but this does not make a tap-root, and is soon
followed by many others from any part of the caulicle, or even from the
stem above, giving it the appearance of having a multiple root.

The root of the Radish is different from any of these; it is _fleshy_.
Often, it tapers suddenly at the bottom into a root like that of
the Morning-Glory with some fibres upon it. It is, in fact, as the
Morning-Glory would be if the main root were to be thickened up by
food being stored in it. It is a primary tap-root. The radish is
_spindle-shaped_, tapering at top and bottom, the carrot is _conical_, the
turnip is called _napiform_; some radishes are shaped like the turnip.

The aërial roots of the English Ivy answer another purpose than that of
giving nourishment to the plant. They are used to support it in climbing.
These are an example of _secondary_ roots, which are roots springing
laterally from any part of the stem. The Sweet Potato has both fleshy and
fibrous roots and forms secondary roots of both kinds every year.[1] Some
of the seedlings will probably show the root-hairs to the naked eye. These
will be noticed hereafter.

[Footnote 1: Gray's Lessons, p. 35, Fig. 86.]

[Illustration: FIG. 11.--1. Tap-root. 2. Multiple root of Pumpkin. 3.
Napiform root of Turnip. 4. Spindle-shaped root of Radish. 5. Conical root
of Carrot. 6. Aërial roots of Ivy.]

It is my experience that pupils always like classifying things under