James Small. 
214 
elusion that both the apical appendage and the “ article antherifere,” 
where it occurs, are produced by a contraction of the polliniferous 
region of the anther, i.e., by a real sterilisation of potentially 
sporogenous tissue. 
E. The Phylogenetic Significance of the 
Styles and Stamens. 
As the complexity of the styles and that of the stamens have 
been shown to be more or less complementary, it is necessary in the 
elucidation of the phylogeny of the groups to consider, not so much 
the two sets of organs separately, as the complexity of the pollen- 
presentation mechanism as a whole. Each tribe will, therefore, be 
examined in order to determine the primitive and advanced sub¬ 
tribes and these will also be examined in order to determine their 
relations with one another throughout the family as far as it is 
possible to elucidate this from the pollen-presentation mechanism 
alone. 
As the Senecioneae appear from the analysis of both styles and 
stamens to be the primitive tribe it will be considered first. The 
Liabinae are undoubtedly specialised in their style (Type III) but 
the types of stamens vary widely (2-9). The chief genus, Liabum , 
has comparatively simple stamens, type 2 or 6, and in the sub-tribe 
as a whole we get somewhat the same range of variation in the 
stamens as occurs in the Vernonieae. 
TI 11 'ee of the chief genera, Homogyne, Crenumthodium, Alciope 
and also Luina, in the Tussilagininae, show styles of type II. In 
Luina this is combined with stamens of types 8 or 10 and in Alciope 
with types 6 or 7, giving in both cases a relatively complex pollen- 
presentation mechanism. In Homogyne and Cvemanthodium style 
type II occurs with stamens type 3 or 4, so that here the mechanism 
is less complex. Now Crenianthodium, although separated from 
Senecio as a distinct genus by Bentham and other systematists, is 
included in that genus by Franchet (23) who places it in the group 
Ligularia of Senecio, dividing that group into A-Cremanthodium and 
B-Eu-ligularia. It is really a mere matter of opinion, as even those 
who uphold the genus admit that it passes into the Ligularia group 
through such species as Crenianthodium plantagiueum, Moor., which 
sometimes shows as many as five capitula instead of the solitary one 
which characterises the genus, and also through Senecio calthcefolius, 
Hk.f. (= Crenianthodium Hookeri, C.B.C.), which shows from one 
to four capitula. The only other distinction lies in the “ nodding” 
