POLLEN FLOWERS 



105 



concerned with the production not only of good fruit but also of seeds capable of 

 germination for the propagation of the stock. At the present time fig-trees are no 

 longer produced from seeds, but from cuttings, so that caprification is superfluous. 



As already mentioned (pp. 64, 67-8), Hermann Miiller (' Alpenblumen,' pp. 479- 

 511) arranged entomophilous flowers in nine classes, and these must here be described 

 at some length. 



I. Pollen Flowers (Po). 



These are flowers which oflfer only pollen to their visitors, as, e. g. in species of 

 Anemone, Papaver, Hypericum, Helianthemum, Rosa, Solanum, Verbascum, and 

 Sambucus. They are all very simple, regular in form (radially symmetrical), and 

 their often very abundant pollen is usually freely exposed (Fig. 18). 



1 



Fig. 18. Pollen Flmvers. (i) Hypericum : a, stigmas, (i) Solanum tuberosum L. : a, anthers 



J, stigma. 



This does not exclude the possibility of some visitors obtaining sugary juices 

 by boring into the tissue of the base of the flower. Among pollen flowers must also 

 be included such anemophilous plants as receive occasional j. 



visits from insects, e.g. species of Artemisia, Plantago, and 

 Thalictrum, the inflorescences of which are so conspicuous 

 that insects now and then appear as guests, and also such 

 anemophilous flowers as possess an odour, however slight, 

 that attracts visitors. Plants thus intermediate between the 

 anemophilous and entomophilous types I have called 

 'wind flowers (W)' ('Die Besucher derselben Pflanzenart 

 in verschiedenen Gegenden,' I, pp. 9 and 10). (Cf. p. 69, 

 note.) Anentomophilous (Ane) may serve as the English 

 equivalent. 



On the other hand, nectarless flowers in which the 

 pollen is only visible after special manipulation, e.g. Saro- 

 thamnus scoparius. Genista tinctoria, and others, are not to be 

 regarded as pollen flowers, but are well-marked bee flowers 



(Fig- 19)- 



As Hermann Miiller has explained ('Alpenblumen,' 



p. 479), the chief floral colours are represented among pollen 



flowers. The following examples illustrate this : — 



Fig. 19. Genista tinctoria^ 

 L. A Pollen Bee Flower (ex 

 ploded), (After Hermann 

 Muller.) 



