STRUCTURE AND LIFE HISTORIES 
386). One of the petals, the lip, presents a greater variety 
of form in the various species than do the other petals. At 
its base is the column, composed of the style, with which 
are fused the one (or sometimes only two) stamens (Fig. 
387). Except in the lady's slipper (Cypripedium), and its 
FIG. 382. Sabal palmetto. (In the right distance a barragona palm). 
Cuba. 
nearest relatives, the pollen adheres in masses or pollinia, 
as in the milk- weed. The stalked pollinia adhere to visit- 
ing insects, sometimes to their eyes, and are thus trans- 
ferred from one flower to another. 1 
1 For details of the wonderful contrivances for cross-pollination, the 
student should consult some larger treatise, such as Darwin's "Cross- 
fertilization of Orchids." 
