534 



D1COTYLEDONES. 



emarginate ligules ; the stamens have a horn-like appendage, pro- 

 jecting upwards from the back of the filament. The fruitlets are 

 hollow below. Anchusa (Alkanet, Fig. 572). The corolla is 

 salver-shaped; the ligules small, hairy protuberances. A. (Ly- 

 copsis) arvensis has an S-curved corolla-tube. Myosotis (Forget- 

 me-not, Fig. 573) ; rotate corolla, with small (yellow) protuber- 

 ances in the throat ; scorpioid cyme without floral-leaves ; fruitlets 



O 



FIG. 572. Anchusa, officinalis : A diagram; the bracteole a is suppressed (dotted); 

 supports a flower. B, C Myosotis, the fruit, entire and with the calyx in longitudinal 

 section. I>, F Alkanva tinctoria: T> the corolla opened (y) ; e the ligule ; /, g the anthers; 

 E gynosceum (f); F fruit, with three fruitlets; i an aborted locnlus ; li disc. 



flat. OmpJialudes ; fruitlets hollow at the back, with a scarious, 

 turned-in, toothed edge. Asperugo (Mad- wort); the calyx grows 

 after flowering, becoming large, compressed, and deeply bifid. 



CROSS-POLLINATION is most commonly effected by insects (especially bees). 

 There are a great many contrivances for pollination; some flowers are protan- 

 drous (Echium vulyare, Borago officin.), others are heterostylous (long- and short- 

 styled: Pulmonaria officin.) ; the corona (ligules) is a protection against rain, 

 and excludes certain insects. Some are barren when self-pollinated (Pulmonaria 



