The Making of Species 
not only functionless but absolutely injurious, as 
in the case of the comb and wattles of the jungle 
cock and his domestic descendants, which merely 
serve as a handle for enemies to seize. 
Cunningham asserts that the only objection to 
his theory is the dogma that acquired characters 
cannot be inherited. This assertion is, however, 
not correct. It is, indeed, a very serious objection 
that all the evidence available seems to show that 
acquired characters are not inherited, but this is 
by no means the only difficulty. 
Before mentioning these further objections, let 
us say a word on the subject of the inheritance 
of acquired characters. Mr Cunningham himself 
compares the formation of a splint or spavin 
in a horse as the result of special strain, to 
the acquisition of secondary sexual characters, 
Unfortunately for Cunningham’s theory, but 
fortunately for mankind in general, spavined 
horses and mares do not beget spavined off- 
spring. If, then, spavin is not inherited, is it 
not unreasonable to assert that the thickening 
of the bone that develops on the head of a 
butting animal is inherited ? 
Another objection to Cunningham’s theory is 
that many birds which show off their plumage 
most vigorously possess no ornamental plumes. 
As Howard has recorded, many of our dull- 
coloured British warblers show off in the same 
manner as bright-coloured birds do. If the 
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