POLLE NATION: HETEROSPORY. 361 



661. Cypripedium or lady-slipper. One species of the lady-slipper is 

 shown in fig. 465. The labellum in this genus is shaped like a shoe, as one 





Fig. 458- 

 A group of jacks. 



can see by the section of the flower in fig. 465 . The stigma is situated at st, 

 while the anther is situated at a, upon the style. The insect enters about 

 the middle of the boat-shaped labellum. In going out it passes up and out 



