84 OUR NATIVE ORCHIDS 



upper surface of the knob very sticky. He also found that 

 the whole knob or rostellum would come off if it were shoved 

 very slightly upward and backward, and that its under side 

 was also adhesive, and would dry fast to anything to which it 

 stuck. 



He examined flowers while still in the bud, and found 

 that, before the flower expands the anther opens, and exposes 

 the pollen masses. 



These lie in round grains that stick together in fours. 

 Each group of four is tied around by a fine elastic thread, 

 and the sum total of all the threads is collected into a bundle 

 that looks, under a magnifying glass, like a brown spot in 

 front of the pollen. It is this bundle or knot of threads that 

 becomes pressed against the knobby rostellum in the bud, 

 the moment the anther opens. It sticks fast, and anything 

 that will remove the rostellum will naturally pull the pollen 

 masses out of their sockets in the anther. 



As the flowers stand out almost horizontal!}' from the 

 stem, the curiously shaped lip hangs out invitingly. The 

 lower portion of it is rounded into a pouch in which the 

 nectar lies, and the lip end is hinged and forms a landing 

 place for insects. 



As the insect alights on this porch or clings to its swinging 

 hinged tip, he bends down into the honey cup and takes his 

 fill, then flying out and upward, his head strikes the sticky 

 under surface of the knob-like rostellum and drags off the 

 cap, to the upper surface of which the pollen is adhering. 



His observation of the insect visitors to Epipactis latifolia 



