CH. XI] B. MORPHOLOGICAL 125 



in either of these respects. Yet both the follicle and the achene 

 show perfection — the one in its complete closure, the other in 

 opening from one extreme to the other of the wall, and only on 

 one side. Why, again, did selection cause only one side of the 

 follicle to open, and that exactly, while the pod opens with equal 

 accuracy upon both sides? No ada^^tational difference between 

 them can be shown to exist. 



Ovules, again, cannot be developed in stages, from nothing to a 

 complete ovule, though the reverse process is possible, but 

 usually leaves some rudiments, which are not found in an achene. 

 Nor can one imagine any transition — direct or through some 

 intermediate form — from a multi-ovulate dehiscent fruit to a 

 one-ovulate indehiscent. Nothing but mutation, and that con- 

 siderable, could effect such a change, and as there is no adapta- 

 tional reason behind it that one can conceive, a single mutation is 

 more probable than a series of mutations. And again the morpho- 

 logical question comes up — why are all follicles structurally 

 alike, and why were they produced in preference to pods or to 

 achenes? In the author's opinion, nothing but a complete muta- 

 tion of considerable size can have produced the difference, and 

 nothing but inheritance from a common parent can have caused 

 it to be shown by whole groups of species, genera, families, etc. 

 In other words, differentiation is the most probable explanation, 

 and natural selection in any direct form is out of the question. 



Other types of fruit lend themselves to similar explanations, 

 in which adaptation has but little if any part. It is, when one 

 comes to think about it, a matter of extraordinary difficulty to 

 show that the different fruits have any real adaptational value. 

 What is the value to a tree like a Dipterocarp, which grows in 

 dense practically windless forest, and often in a forest of one 

 species only (pure stand), of its characteristic winged fruit? How 

 could it, under the circumstances, have been developed by 

 natural selection? Under gradual variation, all the sepals would 

 vary alike, so that it must have begun with a mutation. And 

 why should this be small, and not complete? In any case the 

 calyx does not appear till the tree is perhaps thirty years old, and 

 can anyone pretend that the struggle for existence between trees 

 of this age and size is so severe that natural selection can get a 

 leverage upon so slight a difference as the fact that two or three 

 of the sepals are slightly longer? If anything, as the elongation 

 will use more material, the longer sepals are more likely to be 

 disadvantageous. If one say that the winged fruit gives the 



