Origin and Development of the Compositet. 73 
shows denticulate epidermal cells, and below these in many cases 
cells with spiral filaments (Fig. 14). 
Fig. 11. Duplex hair of Senecio vulgaris ; Fig. 12. Elater cells of Chrys¬ 
anthemum Leucanthemum; Fig. 13. Ditto of Maruta Cotula; Fig. 14. Endocarpal 
filaments and denticulate epidermal cells of Lactuca scariola ; Fig. 15. Endo¬ 
carpal fibril of Cirsium lanceolatum; Fig. 16. Elater cell of Trixis. Figs. 12-15. 
after Macloskie, Fig. 16 after Lavialle. 
The Cynareae vary ; some have duplex hairs as in the Astereae, 
others have simple hairs, and others again show endocarpal fila¬ 
ments as in the Cichoriese (Fig. 15). Centaurea shows simple 
hairs. The lnuleae have duplex hairs similar to those of the 
Astereae but with obtuse tips. In view of the suggestion that 
Cavea (Plucheinae) is an intermediate type between the lnuleae and 
Cynareae (see Chap. IV) it is interesting to note that the typical 
Asteroid hairs occur in Pluchea foetida (Plucheinae) as well as in 
the Cynareae. 
One of the most interesting points is the variation in the 
genus Trixis of the Nassauviinae. According to Lavialle (op. cit.) 
Trixis Lessiugii, T. verbascifonnis and T. tnollissima have one or 
two-celled simple hairs, but T pallida, T. Hieronymi, T. ochroleuca 
and T. brasiliensis have simple hairs with spiral elaters (Fig. 16). 
If this is read in connection with the suggestion of Trixis as the 
primitive genus in the Nassauviinae (see below, Sect. C.) the 
phyletic value of these hairs becomes obvious. 
