Wild Flowers East of the Rockies 79 



PINK LADY'S SLIPPER; MOCCASIN FLOWER 



(Cypripedium acaule) has solitary flowers surmount- 

 ing a scape from 8 to 12 in. high; lip large, drooping, 

 pink, with a slit in front, instead of a circular open- 

 ing as in the others. It frequents dry woods and may 

 be found from southern Canada, southwards. 



This is the most common of the Lady's Slippers 

 and too in my mind is not less beautiful than any of 

 the others. I rather think that if it were as rare as 

 the Ram's Head, it would be regarded and prized as 

 one of the most beautiful and exquisite flowers that 

 we have. Among all our plant families none are so 

 exclusively adapted to fertilization by insects as 

 those comprising the orchids. The flower of the pre- 

 sent species is a very ingenious contrivance; it is 

 fertilized by the common bumblebee. He knows 

 there is plenty of food in the interior of the pink sac. 

 The only chance for entrance is through the fissure 

 in the front; it requires considerable pressure to 

 force his burly frame through, but at length he suc- 

 ceeds and the aperture closes behind him. After 

 eating his fill he takes the easiest way out, towards 

 the base where he can see two spots of light. As he 

 forces his way through the narrow passage he comes 

 in contact with a sticky stigma, armed with in-curv- 

 ing hairs which remove any pollen he may have on 

 his back; as he continues his struggle out he reaches 

 an anther blocking the passage and waiting to clap 

 its load of pollen on his back. Thus when he 

 emerges he is fully charged with pollen to deposit 

 on the stigma of the next flower visited. If you 

 notice you will see that bees continue feeding on the 

 same species of flowers and will pass by those of 

 other species. This habit is Nature's protection 

 against leaving the pollen of one plant at the door of 

 another entirely different species, where it would 

 do no good. 



