88 CONSERVATOR OF SURGEONS’ MUSEUM [ch. iv. 
scientific point of view consists in its having been 
so. This work had the effect at the time of 
raising its author to the highest position in Britain 
as an ornithologist. In the prefaces to these 
volumes he fully explains and vindicates the 
principles on which his system of classification, 
entirely differing from the classification of previous 
ornithologists, was founded. 
But since that time the advance in ornithology, 
in every department of it, has been enormous. 
Many have followed the line of treatment initiated 
by MacGillivray, and most writers, since the 
publication of the Origin of Species , have gone 
much further, in the light of the principles of 
evolution and natural selection. Every organ and 
feature of the bird, both internal and external, has 
been made the subject of the most minute examina¬ 
tion, with results directly bearing on the principles 
of classification. 
He betrays oftener than once in his works a 
prophetic consciousness that, while he felt he was 
groping in the dark, the dawn of greater light was 
near; but how far he would have been able to 
accept the principles of Darwin may be uncertain. 
His belief in the separate creation of each species, 
and in its permanency as so created, appears to 
have been strong, when the introduction to the first 
volume of his History of British Birds was written. 
In it he says: “ Species alone exist in Nature,” 
while “ genera, families, orders, and all the mediate 
sections of a class must ever remain fluctuating; ” 
