18 ON FLOWERS AND INSECTS. [lect. 



see how far we can answer the questions which I 

 began by asking. 



In the first place, the honey attracts insects. If 

 there were no honey, they would have no object in 

 visiting the flower. The bright colour is useful in 

 rendering the flower conspicuous. The platform serves 

 as an alighting stage for bees. The length of the 

 tube has reference to that of their proboscis, and pre- 

 vents the smaller species from obtaining access to the 

 honey, which would be injurious to the flower, as it 

 would remove the source of attraction for the bees, 

 without effecting the object in view. The upper arch 

 of the flower protects the stamens and pistil, and also 

 presses them firmly against the back of the bee. So 

 that, when the bee alights on the stage and pushes its 

 proboscis down to the honey, its back comes into contact 

 with them. The row of small hairs at the bottom of the 

 -tube prevents small insects from creeping down the tube 

 and stealing the honey. Lastly, the small processes on 

 each side of the lower lip are the rudimentary representa- 

 tives of parts, formerly more largely developed, but which, 

 having become useless, have almost disappeared. 



In the Deadnettle, it would appear that the pistil 

 matures as early as the stamens, and that cross-fertili- 

 zation is attained by the relative position of the stigma, 

 which, as will be seen in the figure, hangs down below 

 the stamens ; so that a bee, bearing pollen on its back 

 from a previous visit to another flower, would touch 

 the pistil and transfer to it some of the pollen, before 

 coming in contact with the stamens. In other species 

 belonging to the same great group (Labiatae) as Lamium, 

 the same object is secured by the fact that the stamens 



