BOTANICAL SUBJECTS. 365 



of the frond of Porphyra. There is no escaping the conchision 

 tliat ovules are buds, for they repro(Uice a branch in due course, 

 and in cases of parthenogenetic ovules, a Ijranch identical with 

 that derived from axillary buds. The axillary bud l^eing a 

 branchlet of the leaf becomes, ipso facto, a tooth, and as such, is 

 one and the same thing with the ovule, which is a tooth of the 

 carpel. There is no escaping the conclusion that ovules corre- 

 spond to the glands on the tips of the teeth of leaves, for if wc 

 once recognise the identity of carpel and leaf, the marginal ovule 

 and the tooth-gland fall into identical positions, and can be no 

 other than homologous parts. It will thus be seen that the gland 

 on the leaf -tooth falls also into its proper place as the terminal hud 

 of an atrophied branch. These leaf-teeth, originally cladophvl 

 lobes, are subject to total suppression. In the Agaves tlie\ are 

 very prominent as horny or woody teeth, and the terminal luid of 

 tlie leaf is a formidable spine, but in A. jyruinosa* the serrations 

 are minute, and in A. attemiata and EUemeetiana, the fleshy 

 leaves are destitute of teeth, and the terminal spine, which would 

 correspond to a tei-minal bud, is changed into a seta. 



Twelfth. — That the contraction of a leaf -blade may cau.se tlie 

 fusion of all the teeth-glands, and so give origin to the amalga- 

 mated glands on the petioles of the cherry, the plum, the peach, 

 the passion flower, the Erythrina, and others. These amalgamated 

 teeth-glands of course would lie the homologues of amalgamated 

 ovules, and as such would be the homologues of anthers and of 

 sporangia. 



Thirteenth. — That, if the seed is a bud, it must follow that 

 the cotyledons are only bud-scales, or stipules, used for purposes 

 of storing nutriment, this bud being destined to lead an indepen- 

 dent life. They correspond in function to the albumen of the 

 egg, and to the function of leaves. The albumen proper belongs 

 to every seed, which is absorbed either during the lipening of 

 the seed or during germination. The axillary bud naturally does 

 not require this storage, because it derives its nutriment from 



* Eoyal Gardens, Kptv. 



