MORE MARBIAQE CUSTOMS. 



129 



way cross-fertilisation is rendered almost a dead 

 certainty. The result of these various clever 

 dodges is that the orchids have become one of 

 the dominant plant-families of the world, and in 

 the tropics usurp many of the best and most 

 favoured positions (Fig. 24). 



Darwin has written a most romantic book on 

 the numerous devices by which orchids alone 

 attract insects to fertilise them. I will say no 

 more of this family, therefore 

 — the highest and strangest 

 among the threefold flowers 

 — save merely to advise those 

 who wish to know more of 

 this curious subject to look 

 it up in his charming volume. 

 Instead of pursuing the 

 ms.tter at issue further, I 

 will give one final example 

 in an opposite direction. 



An opposite direction, I 

 say, because all the threefold 

 flowers we have hitherto been 

 considering are examples 

 of a strict upward move- 

 ment of evolution. Each group we have ex- 

 amined has been higher and more complex 

 than the group before it. But I will now show 

 you an instance, if not of degeneracy, at least of 

 extreme simplification, which yet produces in 

 the end the best possible results. This instance 

 is that of the common English arum, known to 

 children as cuckoo-pint or "lords and ladies" 

 (Fig. 25). 



9 



FIO. 24. — THE TWO 

 POLLEN-MASSES, VERY 

 MUCH ENLARGED. 



