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 different heads, and it is a good exercise. The following table may be made of the roots they have studied, adding other examples. Dr. Gray says that ordinary roots may be roughly classed into fibrous and fleshy.[1] Thomé classes them as woody and fleshy.[2] [Footnote 1: Gray's Lessons, p. 34.] [Footnote 2: Text-book of Structural and Physiological Botany. Otto Thomé. Translated and edited by Alfred W. Bennett, New York. John Wiley and Sons. 1877. Page 75.] ROOTS. | ------------------------------------------ | | _Primary_. _Secondary_. | | -------------------------------- | | | | _Fibrous_. _Fleshy_. Roots of cuttings | Aërial roots. ------------------- Sweet potatoes.[3] | | _Simple_. _Multiple_. _Simple_. Morning Glory. Pumpkin Carrot. Sunflower. Radish. Pea. Turnip. Bean. Beet. Corn. Corn. [Footnote 3: The Irish potato will very likely be mentioned as an example of a fleshy root. The teacher can say that this will be explained later.]