Origin and Development of the Compositez. 133 
Hieracium, except II. PiLusella, is in accordance with the suggested 
recent origin by mutation of the thousands of micro-species 
described in that genus. 
Although no palaeobotanist has yet suggested an affinity between 
any of the earlier fossil Coinpositae and Senecioneae, it is significant 
that an unidentified species of Senecio is described by the Reids 
from the lowest beds (Middle Pliocene) examined by them. Quite 
a number of the fruits figured by Heer and Saporta might well be 
ascribed to Senecio and its allies. 
The presence of the Cynareae in the Mediterranean region in 
Miocene times and the absence of any clear evidence of their develop¬ 
ment in the Oligocene is in accordance with the date of origin as 
deduced from the structure and geographical distribution of the 
tribe. They are more restricted in area and more specialised in 
structure than the Cichorieae, so that the action of the Law of Age 
and Area, as shown by the present distribution, receives some 
corroboration in this case from the fossil evidence. It will be 
noticed that both Centaurea and Carduus occur in the Upper 
Pliocene, so that the development of the Cynarea 2 at that date is in 
accordance with the greater age of the two sub-tribes represented. 
The leaves of Parthenites prisons are so much like the 
characteristic leaves of species of Chrysanthemum that^they may be 
used as corroborative evidence for the statement in Chap. X, D, 
that the main genera of the Chrysanthemidinae are older than those 
of the Anthemidinae, while the suggestion that the tribe arose before 
the Cichorieae is not invalidated by the simultaneous occurrence of 
representatives of both tribes in the Lower Oligocene. The 
coroniform pappus of Hyoserites Schullzii from the Upper Miocene 
may be another indication of the presence of the Anthemidea 2 in 
these early times, while the occurrence of living species of the tribe 
in the early glacial deposits is further evidence of an antecedent 
development of the group. 
The Inuleae are represented only by an unidentified species of 
Helichrysum from the Middle Pliocene. Such meagre evidence is 
of little phyletic value; that the fruit belongs to the Gnaphaliinae is 
in accordance with the views previously expressed on the primitive - 
ness of that sub-tribe, while the absence of other representatives 
of the group, especially of Guaphalium, is easily accounted for by 
the small size of the fruits and the alpine habitat of most species. 
The Astereae are represented only by the leaves of one living 
species and the fruits of another. As they are both Pleistocene 
they give no interesting data. The well confirmed derivation of 
the Eupatorieae from the Astereae, however, lends a douk 
