Page:An introduction to physiological and systematical botany (1st edition).djvu/141

 Rh having, as mentioned above, so many pairs of roots, the growth of some of which is always going on, has hitherto not been found to survive transplantation at all.

''Iris tuberosa, Sm. Fl. Græc. Sibth. t. 41, has a root very analogous to these just described, but I. florentina and I. germanica, t.'' 39 and 40 of the same work, have more properly creeping roots, though so thick and fleshy in their substance, and so slow in their progress, that they are generally denominated tuberous.

6. Radix bulbosa. A Bulbous Root, properly so called, is either solid, as in Crocus, Ixia, Gladiolus, &c.; tunicate, tunicata, composed of concentric layers enveloping one another as in Allium, the Onion tribe; or scaly, consisting of fleshy scales connected only at their base, as in Lilium, the White or Orange Lily. The two latter kinds have the closest analogy with leaf-buds. They are reservoirs of the vital powers of the plant during the season when those powers are torpid or latent, and in order to perform the functions of roots, they first produce fibres, which are the actual