MESSMATES, MUTUALISTS, AND PARASITES 87 



broadens into three lobes, of which one curves up on each side, 

 while the third takes a downward course and divides at its end 

 into a couple of curved projections. Just at the place where the 

 stalk expands into lobes a small double projection arises from its 

 upper side, and this serves as a footstool for flies, which are here 



Fig. 1080. Cross-Pollinated Flowers, i, Front view of a fly-pollinated orchid (Phalanopsis Schilleriana); 

 2, column of same, showing bilobed footstool; 3, pollen-masses of same attached to sticky heart-shaped gland; 

 4, side view of pollen-masses; 5, side view showing a fly on the footstool; 6, head of the fly with attached 

 pollen-masses; 7, the same after the pollen-masses have bent forwards; 8 (in vertical section), shows a fly intro- 

 ducing pollen-masses to another flower. 9, Flower of the moth-pollinated Lesser Butterfly Orchis (Habenaria 

 bifolia); 10, the same, with head of a moth (Sphinx pmastri] probing the long spur with its proboscis; n, 

 head and extended proboscis of the moth. 12, Side view of a bird-pollinated flower (Melianthus major] with 

 outer part removed, four stamens and the long curved style are seen; the arrow indicates the way to the 

 honey-containing spur. 13, Flower of a moth-pollinated honeysuckle (Lonicera Etmsca) with long honey-con- 

 taining tube; the arrow shows how to reach this the rounded stigma and stamens must be successively touched. 

 2 > 3 4 6, and 7, slightly enlarged ; the other figures natural size. 



the invited guests. In the middle of the flower, just behind the 

 footstool, may be seen a short projecting "column", the rounded 

 top of which is constituted by a short stamen, immediately beneath 

 this being a deep hollow, the stigma. The pollen is aggregated 

 into two masses (pollinia), attached to a little curved plate, which 



