56 INTRODUCTION. 
that divergence from one form, as now witnessed, usually is and 
must be approximate convergence towards and with some other 
form. ‘To illustrate this counterpoise of convergence, as fully and 
clearly as Mr. Darwin has illustrated bis principle of divergence, 
would demand a volume by itself. One very simple example 
must here suffice to show what is meant by convergence. Let it 
be supposed that in some genus of plants there are two species 
respectively with ovate leaves and linear leaves; these two forms 
of leaf being part of their specific characters or differences. It 
would be a simple divergence, such as really does occur in nature, 
if a variety of either species should be found with lanceolate 
leaves,—an intermediate form of leaf. In such a case, just to thie 
extent to which the variety diverges from one species, it approxi- 
mates towards the other species. Aud if varieties with lanceolate 
leaves should occur to both species, the convergence would be 
complete between the two, so far as the one simple character of 
lanceolate leaf is concerned. 
Any number or kind of other characters might be taken in 
like manner. Let any actual variation in any plant be taken, 
and the probability is great almost to certainty, that the so-far 
divergence from its own specific type is more or less approximately 
a convergence with some other type, whether belonging to the 
same or to some other genus. The similarities among plants are 
equally numerous with the dissimilarities. The convergences may 
be found to equal the divergences. Mr. Darwin thinks that 
species arise through accumulated divergences. Is it not as true 
that they are known by (not to say, result from) the convergence 
of numerous characters,—the classic—ordinal—generic—specific 
characters all converging in the individual plants put together as a 
species ? Why should it be declared that all these combinations 
of character in each species have resulted from or through 
divergence solely ? 
If divergence and convergence both be admitted—and truly the 
one seems as visible in nature as is the other—the two processes 
might reasonably be supposed to keep up, and perhaps to have 
ever kept up (that is, so far as we see or trace), an approximate 
