82 James Small. 
of the nature of another set which is present, seems to the writer 
very appropriate. 
The five-point insertion of the setae and the frequency with 
which five or ten occurs as the number of paleae or aristae is quite 
explicable by the simple physiological fact that the food supply is 
naturally greatest near the five or ten vascular bundles which 
supply the ovary wall in most genera. As these bundles also 
supply the margins of the petals it follows that the paleae and 
aristae, when five, alternate with the petals and thus develop in the 
position of sepals. 
Thus the application of a little microscopy combined with an 
obvious application of elementary physiological facts removes the 
clouds of controversy and lays “the ghost of the hypsophyll” which 
troubled Goebel. 
C. Analysis of the Pappus-Forms. 
Having determined the structure and evolution of the various 
mean types of pappus we can now analyse the distribution of these 
types throughout the family, taking the tribes in the order which is 
suggested by other phyletic data. As the pappus shows great 
variety, sometimes even in the same genus, it will be necessary to 
consider the tribes in some detail. 
Senecionece. In the basal genus, Senecio, the pappus is usually 
copious and setose scabrid, but it varies to simple setose and is 
sometimes barbellato-setose, or of fewer, thicker, almost aristate 
setae, which may be paleaceous at the base, as in § Senecillis 
(—Ligularia glauca, Hoffm.), or the scabrid setose type may be 
paleaceous at the base, as in 5. Grahami , Hook. It may also be 
reduced to very short setae or may be altogether absent. 
The closely related genera, Culcitium, Gynura, Cineraria, 
Emilia and Gynoxys are all setose scabrid or barbellato-setose with 
the setae in one, two or more rows as in Senecio. The genus 
Raillardia, which Hoffman removes to the Heliantheae, and 
Raillardella are plumoso-setose. The other genera are all setose 
scabrid. 
In the Tussilagininae the simple setose type occurs in Tussilago, 
but the other genera are setose scabrid or barbellate. All the 
Othonninae and most of the Liabinae are similar but in some species 
of Liabum an outer row of short, fimbriato-paleaceous scales occurs. 
In the Senecioneae, therefore, all the primitive types, A, B, D, E, 
