14 



SHOWY LADY'S SLIPPER. 



Lady's Slippers belong to that 

 most remarkable of plant families, 

 the Orchids. Orchids are noted for 

 the peculiarity of their blossoms 

 which sometimes take very grotesque 

 shapes. Usually one or more of the 

 petals or sepals are greatly enlarged 

 into a sac, a broad platform or are 

 curiously slashed and subdivided. 

 They are the most highly specialized 

 of all flowers, each dependant upon 

 the agency of certain insects to in- 

 sure their fertilization, some depend- 

 ant upon the visit of just one species 

 of insect ; if that one does not appear, 

 no new seed will be set; only a few 

 years of failure will result in the species being lost to that 

 locality. 



The expedient most often adopted by orchids to prevent 

 useless insects from pilfering the bountiful supply of nec- 

 tar is to have it at the end of a long slender tube or spur; 

 only a long-tongued insect can reach the sweet and it will 

 be found that the one that is best fitted for the purpose is 

 the one that is also adapted to best accomplish the fertiliza- 

 tion of the blossom. For instance the large White-fringed 

 Orchid is visited by a sphinx moth, which has a tongue of 

 just the right length to drain the nectary. As he presses 

 his face into the tube to reach the last drop his eyes come 

 into contact with tiny sticky buttons to which the pollen 

 masses are attached; as he withdraws his head the pollen 

 masses are drawn from their pockets and project forward, 

 one from either eye. Since the moth eye is a large com- 

 pound one, the covering of part of the surface does not ser- 

 iously inconvenience him; he flies away to the next blossom 

 and lo — the pollen masses are in just the right position to 

 be pressed into the stigma of that flower. Some of these 

 processes of fertilization are very complicated ones and are 

 very interesting to study. 



