91 
Origin and Development of the Composites. 
phyletic data, provided that critical tendencies are considered to be 
of as much importance as actual form. Two such tendencies, i.e., 
cohesion and reduction which are fundamental tendencies in the 
other parts of the floret, can he recognised as being ruling factors 
in the development of the paleaceous, aristate and coroniform types 
from the primitive setose types. These lines of orthogenesis are the 
key to the otherwise hopelessly confused mass of variations shown 
by the pappus. 
Many of the points where the pappus-form has a phyletic value 
have been indicated in Section C so that it is only necessary to 
summarise briefly the phyletic value of this part of the floret. 
Senecio is confirmed as the basal genus, by the dominance of 
the most primitive pappus-forms and the occasional expression of 
the two fundamental tendencies above-mentioned. The basal 
position of the Senecioninae is also confirmed by the same facts 
and the lines of evolution leading to the higher types of pappus are 
traced in outlying genera. 
The Liabinae are confirmed as an intermediate stage in the 
development of the Vernonieae and the derivative position of the 
Lychnophorinae is also verified. 
The origin of the Cichorieae from the Senecioninae is confirmed 
and the progressive development of the two critical tendencies 
together with the frequent presence of the primitive types is clearly 
shown. 
There is also evidence in support of the suggested origin of the 
Calenduleae as a reduction product of the Senecioninae. 
The evolution of type M from type E occurs in the origin of the 
Arctotideae, Ursinia again being the basal genus, with the Gorteriinae 
as a progressive variation and the Gundeliinae as a reduced 
derivative. 
In the Anthemideae the tendency to reduction is more strongly 
developed, leading to the frequent absence of the pappus or its 
presence in the form of type N. The occurrence of transitions 
from type A through F to N is evidence in support of the suggested 
origin of this tribe from the Senecioninae. 
The Inuleae show a very marked progressive evolution in the 
pappus forms from the Gnaphaliinae (type A usually) to the Inulinae 
(types A, D, E, F and K), with type A passing into types D, E, F and 
G in the Buphthalminae leading to the Cynareae, where the higher 
setose and paleaceous types are well developed 
In the Cynareae Centaurea is confirmed as the primitive genus 
with the positions of the Carduinae, Carlininae and Echinopsidinae 
