200 BRITISH FLOWERING PLANTS chap. 



Parnassia 



White protandrous flowers, with half- concealed 

 honey. 



P. palustris (Grass of Parnassus). — This species, as 

 its name denotes, inhabits wet and boggy places. It 

 has ten stamens, of which, however, five only bear 

 anthers, while the others secrete honey at the base, and 

 terminate in from eight to seventeen beautiful yellow 

 globular glands. These glands so closely resemble drops 

 of honey that it is difficult to believe they are perfectly 

 dry. They probably serve as sham drops of honey to 

 attract flies. There has been some difference of opinion 

 whether each of these " staminodes " represents a 

 stamen or a group of stamens. I can hardly doubt 

 that the former is the correct view. The five poUini- 

 ferous anthers ripen, not simultaneously, but successively, 

 and as each ripens it places itself right on the top of 

 the stigma, with its back to it, and the pollen is then 

 discharged from the anther on the side away from the 

 stigma, so that it is scarcely possible for any to fall on 

 it ; and this is done by each of the five stamens in 

 succession,^ each taking a day to itself When all five 

 have shed their pollen, on the sixth day the pistil takes 

 its turn. The flower smells of honey in bright sunshine, 

 and becomes scentless towards evening. 



Parnassia offers another case in which, within the 

 limits of the species, the flowers are sometimes smaller 

 and the number of the parts diminished. In the Alps 

 the flowers are from 13-25 mm. in diameter, and 

 these small flowers often have only three stamens. 

 Knuth mentions that flowers from gathered buds 

 observed by him were often homogamous, confirming 

 the just remark by Sprengel, that it is not always safe to 

 conclude from cultivated specimens as to the behaviour 

 of plants in their natural homes. The seeds are very 

 minute, weighing only '00003 of a grain. 



' Bennett, How Flowers arc Fertilised (1873). 



