CNS Le a eo eee ee ee 
Botuny and Zoology. 437 
expressed by Adr. Jussieu in his Cours Hlémentaire Cet peared 
1843 and 1844), and in Gray’s Introduction to Botan t. Test hon 
1858. But the same view is taken in all the fate son of the latter 
work ; even in the first Nee the radicle is spoken of as the first inter- 
node of the stem (p. ipresie and ene? the idea will be found 
a expressed in ae f an earlier date. Dr, Hooker, in the 
note referred to, asse ents to the proposition that “the radicle is rightly 
regarded as an axis” i. e. an ascending axis, “and not a root,” but does 
not agree that it is an internode. To us, the one implies the other. 
Conceiving, as we do, the fundamental idea of the morphology of the 
phenogamous plant to be, that the ascending axis consists of a series of 
superposed internodes, each crowned by a leaf-bearing point or ring Pri 
node), the first internode must needs be that which is crowned 
first leaf or pair of leaves, the cotyledons; and its whole Rerelcpelaink 
confirms this view 
oker notes the curious fact that in Welwitschia flower buds are 
Welwitschia, Wer a dicotyledonous embryo, has ne essentially an 
exogenous stem, i, e. “the vascular system is referable to the exogenous 
. : ” 
tion of the leaves ; nae here are no cross veinlets, thus favoring the 
splitting up of the ‘leaf -into edna, this looks as much or more towards 
Cycadacee and broad-leaved Conifere 
The total absence of anasto omosing veinlets in the leaf, each nerve 
representing a single and independent vascular axis, extending, in Wed- 
hia, from the axis of the trunk to the apex of the dein causes such 
leaves as these and those of Dammara, &c., to “ resemble closely a 
series of parallel uninerved leaves united by cellular tissue, thas a foliar 
expansion of parenchyma traversed by one system of inosculating vessels, 
and the frequent presence of many linear palepoiar in these plan Aits sinus 
to favor this view, as does the mixed character of the foliage of Podo- 
further favor this view.’ That is, in Welwitschia, where this ingenious 
surmise carries a plausibility, i? og it does not when applied to Podo- 
The binary symmetry of Welwitschia, beginning with the cotyledons, : 
is carried airs the inflorescence up to the decussating pairs of bracts 
of the cone and the two leaflets in each woe of ted hermaphrodite 
> perianth. But the stamens are six, at first sight a monocotyledonous an- 
~alogy ; yet they may be led three sets of two, notwithstanding their 
tmonadelphy. 
The flowers are diaecio- polygamous, i i. e., of two sorts, one 
