DOCTRINE OF ORGANIC EVOLUTION = 439 
If we trace the evolution of a given form backward to its 
beginning we come to more and more primitive conditions. 
Mouse-tails, for example, we should derive from ancestors re- 
sembling buttercups in having a shorter torus, more stamens, 
spurless staminodes, and broader leaves. It seems reasonable 
to suppose that these mouse-tail-buttercups left no unmodified 
descendants, and so were not exactly like any living form of 
buttercup, although we might fairly presume that they 
showed more of the relatively primitive buttercup structure 
than of the peculiar mouse-tail features. These buttercup-like 
ancestors would be traced back to progenitors more nearly 
resembling anemonies in which rudimentary ovules still bore 
witness to a previous many-ovuled stage, when also certain 
of the outer stamens were showing only rudimentary anthers 
and were secreting nectar on broadened filaments. The 
step from this form, from which both mouse-tails and anem- 
onies descended, to the marsh-marigold-like ancestors of the 
family, requires us to imagine little more than a previous full 
development of the ovules and anthers which later became 
reduced, and a more ordinary form of filaments and carpels. 
In the above examples of the way an evolutionist conceives 
the changes in a group to have progressed, innumerable 
details of the process have necessarily been omitted for the 
sake of simplicity. Many branches would have to be inter- 
polated if all living genera of the family were to be repre- 
sented, and there is no knowing how many dead branches 
should be shown to make the family tree complete. It must, 
of course, be frankly admitted that the conclusions are largely 
guesswork supported only by circumstantial evidence, for 
no remains of the very perishable ancestral forms of the 
crowfoot family have come to light. Our examples, however, 
are typical of evolutionary schemes in general, and so may 
help our understanding of the theory of evolution. One 
prevalent misconception which it should correct is the notion 
that forms now living are supposed to have been derived from 
ancestors just like other recent forms. On the contrary, 
the kind of conclusions they reach by such means. That such conclu- 
sions are at best far from satisfactory goes without saying; but herein 
lies a challenge to do better, and a spur to further study. 
