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James Small. 
exception of Decachceta, the primitive involucre is the rule. The 
multiseriate type occurs in the chief genera of the Adenostylinae, a 
few others showing the primitive type. 
Helianthece. The primitive involucre is the rule thoughout the 
Heliantheae with only a few exceptions. The difference between 
the pericline and the calyculus is frequently so marked that the 
involucre is known as duplex, even by those systematists who do 
not recognise the essential difference between the pericline and the 
calyculus which is commonly quite foliaceous in this tribe. There 
is so much similarity in the sub-tribes that it is unnecessary to 
consider them in detail with the exception of the Madiinae where 
the calyculus is sometimes absent, and the Galinsoginae where the 
uniseriate pericline and slightly developed calyculus confirm the 
affinity of that sub-tribe with the Helenieae. 
Heleniece. Here the pericline is without exception uniseriate 
and the calyculus is absent or only slightly developed except in the 
more important genera of the Jaumeinae. 
D. Phylogenetic Significance of the Involucre. 
The establishment of a sound view of the morphology of the 
involucre with a definite primitive type enables us, as with the 
pappus, to analyse with some clearness the large number of varieties 
of this part of the capitulum and to obtain some information of 
phyletic value. 
The primitive position of the Senecioneae and Senecio, the 
passage of the Senecioninae into the Vernoniinae via the Liabinae, 
the positions as in fig. 7 of the Othonninae.Tussilagininae, Cichorieae, 
Calenduleae and Anthemideae are all confirmed. The Arctotinae is 
clearly the primitive sub-tribe in the Arctotideae. 
A slight rearrangement of three of the sub-tribes in the 
Inuleae is suggested and corroboration of the position of the others 
obtained. The Centaureinae is confirmed as the primitive group of 
the Cynareae. Trixis as the basal genus (arising from the 
Senecioneae) and the Nassauviinae as the basal sub-tribe of the 
Mutisieae have the involucre in the primitive condition. 
The positions of the sub-tribes in the Vernonieae, Astereae and 
Eupatorieae are confirmed. 
The relative primitiveness of the Heliantheae, the derivation of 
the Helenieae from the Galinsoginae and the advanced position of 
the Jaumeinae are supported by the evidence of the involucre. 
Without exception, therefore, the characters of the involucre 
in the Compositae substantiate the phyletic conclusions given in fig. 
