THE BUSINESS OF LIVING CREATURES 123 
The Observer of Habits. 
Like many of the naturalists ‘ of the old school, 
MacGillivray was strongly attracted to the study 
of habits and behaviour—and of the relations of 
the living creature to its environment—a study 
which, in new- fashioned terminology, is often called 
(Ecology or Bionomics. He liked to study his 
plants in relation to their habitats, in their 
associations; he liked to study his birds as going 
concerns. It was organic life as it is lived in Nature 
—the business of living creatures —that appealed to 
him most strongly. This is very clearly seen in his 
History of British Birds , where so much attention 
is given to the haunts, the diet, the breeding, the 
seasonal changes of the species described. We 
notice also the continual attempt to correlate 
peculiarities of structure — particularly in the 
alimentary system—with peculiarities in habits and 
surroundings. 
MacGillivray occupies an interesting position in 
the history of the science — representing the 
transition between what we may call the Linnsean 
and the Cuvierian levels of scientific description 
and interpretation. 1 By the Linnsean level we 
mean the precise description of the intact creature, 
the corresponding description of its habits as a 
whole, and the correlation of the two. By the 
1 An interpretation of the history of Biology (since the time of 
Buffon) as a gradually deepening analysis is given in Prof. Patrick 
Geddes’s remarkable “ Synthetic Outline of the History of Biology,” 
Proc. Roy. Phys. Soc. Edinburgh , 1885*6, pp. 905-911. 
