Origin and Development of the Compositce. 23 
very varied development of the bilabiate type. The series given, 
Fig. 9,4-9, for Helenium autumnale includes one, Fig, 9, 5, which 
belongs to the palmate type and two others. Fig. 9, 7-8, where the 
abortion of the fifth lobe is progressing to the complete absence 
showm in Fig. 9, 6. 
The origin of the ligulate type by a mutation seems very similar 
to the origin of the fimbriate type described by Trow (84). The 
dropping out of a factor for non-ligulateness in the same way as the 
supposed factor for non-fimbriateness is suggested to have done, 
would, with the addition of the presence of laticiferous vessels, give 
the first of the Cichorieae. 
The Bilabiate Type. 
The presence of the posterior lip of the bilabiate corolla occurs 
markedly in the Mutisieae, where it is characteristic of four of the 
sub-tribes and occurs in Seris (Fig. 10, R) and Ainsliaea (Fig. 10, G) 
of the Gochnatiinae, but it is by no means confined to that tribe. 
In addition to the sporadic appearance of the posterior Up described 
in Xeranthemum, Pulicaria, A n them is t Psiadia, Heterothalamus, 
Erigeron, Centaurea, Denekia, Petasites, Plagiocheilus, Senecio, 
Helenium, Chrysanthemum, Calendula, Dimorphotheca and Grangea 
the phenomenon has been observed by the writer to occur occasion¬ 
ally in the double varieties of Callistephus, Chrysanthemum, 
Helianthus, and Tagetes. 
One of the posterior petals is frequently developed in the ray 
florets in most of the tribes giving a 4-dentate or 4-lobed corolla. 
The usual number of lobes in the anterior lip is three, but these may 
be fused to give two or the lip may be entire. 
In the Senecioneae a posterior lip is sometimes developed in the 
filiform florets of Erechthites and it is a normal character of the uni- 
seriate rays in Brachyglottis, a monotypic genus very closely allied 
to Senecio, Fig. 10, C. 
The posterior lip is also developed frequently in the rays of the 
monotypic genus, Dipterocome, in the Calenduleae (Fig. 10, F). 
In the Arctotidese Cryptostemma shows the character (Fig.10, J). 
In the Anthemideae Anacyclus, § Diorthodon, D.C. has the ray 
entire or 3-dentate but the disc florets although sometimes 
regularly 5 lobed, are frequently bilabiate, the two posterior 
lobes being narrow and erect while the anterior lip has the normal 
form (Fig. 10, K-M). 
In the Inuleae Nanothamnus, another monotypic genus, has one 
of the posterior petals of the hermaphrodite florets split off from the 
