224 



THE FLOWER. 



margin (ray-flowers, with ligulate corolla) , one of which is sepa- 

 rately shown in Fig. 432, are pistillats only : the enlarged and 



extended open part of the 

 corolla (bright yellow in 

 color) serves for attrac- 

 tion, the circle of rays 

 gives the appearance as 

 of a single large flower. 

 The flowers of the disk 

 or whole central part are 

 hermaphrodite, and with 

 narrow tubular corollas, 

 from the orifice of which 

 projects the greater part 

 of the tube of five eo- 



alescent anthers. The pollen is early discharged into the interior 

 of this tube. The style, with somewhat enlarged and brush-like 



tip, at first reaches only to the 

 bottom of the anther-tube : it 

 slowly lengthens, pushes the 

 pollen before it out of the tube 

 (Fig. 433) and into the way of 

 insects of various kind, which, 

 travelling over the surface, con- 

 vey it to older flowers of the same 



head and of other plants. The style, elongating yet more, raises 

 some of the pollen still higher (as in Fig. 434) ; and at length its 

 two branches separate and diverge (Fig. 435), exposing to other 

 pollen the stigmatic receptive surface which until now was un- 

 approachable. 



412. In Parnassia, which has sessile stigmas, their receptive 

 surface is actually not formed until the anthers become effete ; 



FIG. 432 A ligulate female flower of the same, and a, central hermaphrodite flower. 

 433. Upper part of the latter, more enlarged, the tube of anthers projecting from the 

 corolla, and the pollen projecting from apex of the anther-tube, being pushed up by the 

 lengthening of the style beneath. 434. This style now projecting, and some pollen still 

 resting on its tip. 435. Tip of same style (more advanced and magnified); the two 

 branches spreading, still carrying some pollen on the apex of each arm or branch, and 

 by the divergence now exposing the stigmatic inner faces. 



