670 ANGIOSPERMAEDICOTYLEDONES 



480. Xeranthemum Tourn. 



Short conical tip of the style of the hermaphrodite disk-florets covered as far 

 down as the cleft with sweeping-hairs directed obliquely upwards; inner surfaces 

 of the stylar branches beset with stigmatic papillae. There are neither stigmatic 

 papillae nor sweeping-hairs on the styles of the neuter ray-florets. 



1602. X. annuum L. (Sprengel, ' Entd. Geh.,' p. 371; Hildebrand, 'U. d. 

 Geschlechtsverhalt. b. d. Compositen,' pp. 48-50, Taf. V, Figs. 24-30.) Sprengel 

 regarded the ray- florets of this species as female, but Hildebrand says that their 

 ovary, though fairly well developed, never contains an ovule. In the second stage of 

 anthesis the stylar branches diverge and expose their papillose stigmatic surfaces to 

 insects. 



B. Liguliflorae Less. (=Cichoriaceae Juss.) 



Florets all ligulate and hermaphrodite ; style unjointed, its filiform branches are 

 covered with soft hairs, and become reflexed. Kirchner observed that the species of 

 this group present a marked agreement as regards their flower mechanism. The 

 corolla is a tube closed above, before the florets open; it is split on the inner 

 side and produced into a ligulate expansion. When the style grows through the 

 anther-cylinder, it does not push the pollen before it, but becomes covered with 

 this on its outer surface, which is beset with sweeping-hairs. With regard to insect- 

 visits Hermann Muller remarks that as the anther-cylinders usually project for 

 several mm., and the styles as much further, most of the visitors creep about between 

 the ends of the latter rather than over them, so as to transfer pollen with their sides 

 rather than their ventral surfaces. The simultaneous pollination of numerous florets 

 therefore takes place to a less extent than among the Senecionidae and Asteroideae, 

 where heaps of pollen are succeeded by the stigmatic surfaces at the same level. On 

 the other hand, the florets of the Ligulatae can simultaneously receive pollen brought 

 by insect visitors and dust these with their own pollen. 



The yellow-flowered species of the group are visited with special eagerness by 

 bees of the genus Panurgus. 



481. Catananche L. 



1603. C. lutea L. (Murbeck, Vet.-Ak. Ofvers., Stockholm, Iviii, 1 901-2.) 

 Murbeck states that in this Mediterranean species subterranean heads are borne 

 in the axils of the outer leaves of the rosette. These only contain 1-3 cleistogamous 

 florets. 



482. Lampsana Tourn. 



Florets yellow. Style covered externally with sweeping-hairs, which extend 

 a long way down, and closely beset with stigmatic papillae internally. 



1604. L. communis L. (=Lapsana communis L.). (Herm. Mailer, 'Fer- 

 tilisation,' pp. 351-2, 'Weit. Beob.,' Ill, pp. 97-8; Kirchner, ' Flora v. Stuttgart,' 

 P- 733; MacLeod, Bot. Jaarb. Dodonaea, Ghent, iii, 1891, v, 1893; Knuth, 'Bl. 

 u. Insekt. a. d. nordfr. Ins.,' pp. 96, 191 ; Warnstorf, Verh. bot. Ver., Berlin, xxxviii, 

 1896.) In this species the heads are solitary, and not very conspicuous. Hermann 



in 



