296 THE STORY OF PLANT LIFE 



are reddish or dark brown, erect, ovate to lance- 

 shaped, the upper one opposite the lip, broadly lance- 

 shaped, and another of two lateral ones united below 

 the lip. The two petals are dark brown, linear, 

 narrower than the sepals, and the lip is inversely 

 ovoid, not as long as the calyx, large, inflated, slightly 

 depressed below, pale yellow, with purple streaks, 

 with a round upturned end, spreading. The column, 

 which ends in a swollen lobe or deformed stamen, is 

 curved, nearly closing the opening of the lip, is not 

 so long as the petals, the middle lobe ovate, blunt, 

 turned down. There is no spur or rostellum. The 

 ovary is straight. The pollen is granular and sticky. 



The Lady's Slipper is i to ij ft. high, flowering 

 in May and June, and is a herbaceous perennial. 



Unlike other orchids Lady's Slipper has two 

 stamens with two cells. In other types these two 

 are functionless, and the one which is functional is 

 here a shield-like structure. The slipper, which is 

 large, is closed by the column and stigma, having but 

 a very small opening. The opening is horseshoe- 

 shaped. Once inside insects can get out only with 

 difficulty. In the attempt they must touch the 

 stigma below the abortive anther. The lip has the 

 border bent inwards, so that insects can best escape 

 by the ends of the opening or horseshoe aperture, 

 and by so doing they touch the anthers and bear off 

 the pollinia to another flower. The pollen is sticky 

 in this type, which causes it to adhere to insects and 

 to the stigma when brought in contact with it. 



