AS REGARDS SPECIES 
147 
theory — Buffon, Erasmus Darwin, Lamarck, 
Goethe, Treviranus, Etienne Geoffroy St Hilaire, 
and in spite of the many editions of the anonymous 
Vestiges of the Natural History of Creation (by 
Robert Chambers), we do not find that Mac- 
Gillivray ever expressed himself on the new view 
of Nature which was beginning to dazzle men’s 
eyes. There are passages, however, in which we 
can see this at least, that MacGillivray had moved 
away from the Linnsean dogma of the fixity of 
species. To one of the most explicit of these my 
attention has been directed by my colleague Prof. 
James W. H. Trail, and it is of sufficient interest 
to warrant full quotation. It is in MacGillivray’s 
Manual of Botany, published in 1840. 1 
He adheres to the general view of his time in 
such a sentence as the following: “ If we assume 
that a few individual plants, precisely similar in all 
respects, and differing in some respects from all 
others, were originally created, we should call these 
plants and their progeny, up to the present day, 
a species.” But there is a symptom of a change of 
view in what follows. “From various causes, 
individuals that have been derived from these 
original individuals may differ considerably from 
them, and yet be of the same species. . . . All 
species have a tendency to form varieties, insomuch, 
that no two individuals are ever precisely alike in 
all respects.” We have not here any suggestion 
that one species has actually evolved from another, 
1 In the second edition, the passage is in Chapter XXVII., p. 229. 
