Origiti and Development of the Composite. 8 i 
will be obvious to the reader. The main point is that the setose 
type is primitive and the paleaceous, coroniform and aristate types 
derived. 
Fio. 18. Evolution of the Pappus-forms in the Compositse. 
The origin of the plumoso-setose type from the barbellato- 
setose type has been previously noted by the writer (62). The 
origin of type N from type K is a very obvious explanation of the 
well developed fimbriato-paleaceous pappus described by Bdketoff 
(4) in an anomalous Cichorium Intybus. The origin of type N from 
type F explains the frequent mixture of short lacerate squamellae 
with a few awn-like, elongated squamellae, as in Helianthus scabra 
(54). Similarly the origin of the aristae, by the fusion of setae 
explains the frequent variation in the number of aristae, even in a 
genus such as Bideas, where they are an important diagnostic 
character, but in which the aristae vary from two to ten (60). 
It is clear from the above details that the primitive pappus in 
the Compositae has a trichome structure, whatever its homologies 
may be, and that the foliose calyx limb, when it occurs teratologi- 
cally must be regarded as a reversion to a pre-Composite ancestor. 
It will be shown in a later chapter that thet*e is every reason to 
believe that the Compositae were derived from genera such as 
iSiphocampylus in the Lobelioideae, in which the calyx limb is 
frequently very much reduced or even (as in 5. eximius ) altogether 
absent. 
Where a calyx limb is present in addition to numerous hairs of 
various kinds showing similar modifications to those of the pappus, 
as in Tnumfetta(93, and see also 32), there has as yet been no 
suggestion of homologising the hairs of the fruit with the calyx limb. 
Masters’ argument that the absence of one set of organs is no proof 
