v.] RHINANTHUS. 149 



107, which is touched by the proboscis of the bee 

 in passing down the tube to the nectary, and serves 

 as a lever, shaking the whole system of anthers and 

 thus causing the pollen to fall out on to the bee. 



In this species also H. Miiller has observed that 

 there are two forms, a larger one which is adapted to 

 be fertilised by insects, and a smaller one which more 

 frequently fertilises itself. 



In Rhinanthus Cristagalli (the Common Rattle) the 

 anthers are locked together, and the pollen is shed 

 on to the bee, but the mode in which this is effected 

 is not the same. In this species, as in Bartsia odon- 

 tites, the bee has to pass its proboscis between the 

 filaments of the anthers in order to reach the honey, 

 and the space between them is so narrow, that the 

 bee in pressing its proboscis down the tube, presses 

 the filaments apart, thus shaking the anthers, and 

 freeing the pollen. In this species also H. Miiller 

 has observed the existence of two forms. 



In the common Pedicularis (Fig. 108) (Pedicularis 

 sylvatica\ which has been well described by Hilde- 

 brand and Delpino, the arrangement is somewhat dif- 

 ferent. The anthers open on their inner sides, and 

 the edges of the open anther cells on the one side of 

 the flower exactly correspond with, and are applied 

 to, the corresponding edges of the anthers on the 

 other side of the flower ; each pair of anthers thus 

 forming as it were, a closed box. The outer sides 

 of the anthers are slightly attached to the walls of 

 the hood. But the sides of the hood are somewhat 

 too near together to admit the head of the humble- 

 bee, and the insect therefore, in order to reach the 



