214 STUDY OF NATURAL HISTORY. 
Here we have first to bring into practical use the 
theoretical distinctions of analogy and affinity, 
already touched upon. If the contents of one 
genus appear to represent, in some few remarkable 
peculiarities, the contents of another ; and if this can 
also be traced through a third or a fourth ; we are 
immediately impressed with a conviction that this co- 
incidence is the effect of design. It is clear that these 
resemblances, however strong, cannot be relations 
of affinity ; because they occur in different circles, 
which would be broken up and destroyed, if these 
objects of resemblance were taken out and grouped 
by themselves. An example of this will best show 
its effect, and the violence it would commit on the 
law we have set out with. The most inexperienced 
ornithologist perceives a resemblance, more or 
less strong, between the cock, the wattle bird, 
the carunculated starling, the cassowary, and the 
wattled bee-eater. All these, in fact, at first sight, 
are immediately recognised by a head and face more 
or less naked, and ornamented with fleshy crests or 
wattles. Yet, if we concluded that this resemblance 
or relationship was one of affinity, and therefore 
proceeded to take all these birds out of the present 
groups they stand in, and place them in one by 
themselves, what a heterogeneous mixture should 
we have! Nor would this be all: the respective 
circles in which each of these types now stand, would 
of course be broken up, and another group would be 
formed of the wattled birds alone, which would be 
any thing but circular. Resemblances like’ these, 
as we known from experience, will be found in every \ 
natural group. When these groups are remote, we 
