286 CONCLUDING BEMAKKS. CiiAP. IX. 



degree but in many ways, with the preservation of those 

 variations which were beneficial to the organism under 

 complex and ever-varying conditions of life, transcend 

 in an incomparable manner the contrivances and 

 adaptations which the. most fertile imagination of man 

 could invent. 



The use of each trifling detail of structure is far 

 from a barren search to those who believe in natural 

 selection. When a naturalist casually takes up the 

 study of an organic being, and does not investigate 

 its whole life (imperfect though that study will ever 

 be), he naturally doubts whether each trifling point 

 can be of any use, or indeed whether it be due to any 

 general law. Some naturalists believe that number- 

 less structures have been created for the sake of mere 

 variety and beauty, — much as a workman would make 

 different patterns. I, for one, have often and often 

 doubted whether this or that detail of structure in 

 many of the Orchideae and other plants could be of 

 any service ; yet, if of no good, these structures could 

 not have been modelled by the natural preservation of 

 useful variations; such details can only be vaguely 

 accounted for by the direct action of the conditions of 

 life, or the mysterious laws of correlated growth. 



To give nearly aU the instances of trifling details 

 of structure in the flowers of Orchids, which are cer- 

 tainly of high importance, would be to recapitulate 

 almost the whole of this volume. But I will recall 

 to the reader's memory a few cases. I do not here refer 

 to the fundamental framework of the plant, such as 

 the remnants of the fifteen primary organs arranged 

 alternately in the five whorls ; for almost everyone who 

 believes in the gradual evolution of species will admit 

 that their presence is due to inheritance from a remote 

 parent-form. Innumerable facts with respect to the 



