192 PHILOSOPHICAL NOTES ON 



BO that every year it shifts its place, much as grasses and certain lilies 

 do. When the tubercles of these orchids are deep in the earth 

 they send upwards a root-like stem, which produces roots only 

 until it reaches the light, and then deyelops only leaves. Lilium 

 Jjeicliilini does the same thing. Its underground shoot throvrs out 

 roots only until it reaches the surface, when leaves are produced 

 and no roots. Curiously enough, its bulbils emerge from the 

 axilla of one of the roots, which are often verticillate, like the 

 leaves of many lilies. 



14. Lilium Philadeljjhicum has either alternate or verticillate 

 leaves. At the base of the stem, above the bulb, it has Yerticillate 

 roots. 



15. Lilium croceum, in the underground part of its stem, gives 

 off whorls of roots, and sometimes a bulbil from their axillae just 

 as a L. htdhifentm would do from the axillae of its leaf-nerves, 

 these in the upper part of the stem being the homologues of the 

 roots in the lower part. Other liliums do the same.* 



16. We should not lose sight of the fact that in the beginning 

 of time there was no such thing as ground roots, or roots of any 

 sort, but only leaves. In reality the size or breadth of a leaf does 

 not change its nature. It is the petiole, midrib, and veins which 

 count most, for we can have leaves of immense breadth, and leaves 

 which are mere veins, just margined, and others where the margin 

 wholly aborts, as in Ferula, and in the submerged leaves of 

 Eanunculus Skiid' Cdbomha. In the latter the submerged leaves are 

 indistinguishable from thready roots. Therefore, when we speak 

 of a bud being axillary, we really mean the axilla of the petiole, 

 or midrib, as the^case may be, so that there would appear nothing 

 very preposterous in considering the underground bulbils of Lilium 

 croceum or^ Leichtlini as axillary buds of underground leaves 

 (roots). 



17. The j^idea'-of the homology between the roots and leaves is 

 supported by the following facts : — . 



(a.) The verticillate roots on the stem of Lil. Fhiladelphicum 

 and others corresponding to the verticillate leaves ; 



(Zy.) The axillae of stem-roots producing bulbils in Lil. 

 longiflorum, croceum, and Leichtlini, as do the leaves of 

 Lil. Tigrinum,-f and others. 



* H. J. Elwes' " Monogr. on the genus Lilium." 



■(■ I have not had the opportunity of examining lily plants in their green 

 state and therefore what I state may require verification, or rejection.- I 

 only judged from H. J. Ehves' monograph. From these plates it is im- 

 possible to make out -whether the bulbil is subtended by a root or hy an 

 atrophied tract. In the potato, I think the underground bud is snrroimded 

 by roots. 



