July, 1915. The Queensland Naturalist. 
11 
to-day ; we are woefully ignorant of the real origin of 
variations. That remarkable form of variation known as 
mutation was scarcely recognised by the old scientists. 
Darwin laid most stress on the continued selection of small 
and often trivial variations, but we now know that nature 
leaps as well as creeps. vSir Oliver Lodge, indeed, somewliat 
recklessly says : “ So far from nature not making jumps, 
it becomes doubtful if she does anything else. Her hitherto 
placid course, more closely examined, is beginning to look 
like a kind of steeplechase. 
Systematists sometimes surprise us with their notes on 
variation. Agassiz found with his Echinoderms, as did 
Darwin with the Cirripedes, that variations were so great 
as almost to defy classification. And this is apparent in 
practically every branch of science. If a large amount of 
identical material is given to two men, aptly called Professor 
Splitter and Doctor Lumper (to borrow American terms), 
the former will probably make three times as maii}^ species 
as the latter. 
Many variations are not to be wholly analysed as essential 
or even of partial utility to organisms. In the world of colour, 
particularly, there is much that may be looked upon as 
merely due to the exuberance of life and casual chemical 
processes. One might almost as well define on utilitarian 
lines the interaction of atmospheric dust with sunset glories 
as seek to map out a useful colour scheme in the variable 
foliage of a coleus or a caladium. On this point we may 
quote the authority of Darwin. Speaking of the colours 
of certain coral fishes Starr Jordan comes to a similiar 
conclusion. The theories of recognition, nuptual, warning, 
and mimetic colouration do not account for everything. 
Bateson VTites : I feel quite sure that we shall be rightly 
interpreting tlie facts of nature if we cease to expect to find 
purposefulness wherever we meet with definite structures 
or patterns. Hugo de Vries says that mutability 
seems to be free, and not restricted to previously determined 
lines.” He notes that variations may be due to internal 
historical causes and to external causes, such as nourishment 
and exchanging environnrent. They may be, broadly speak- 
ing, of three kinds : the appearance of new charactei's ; the 
reappearance of latent characters ; the disappearance of 
existing characters. A much more intricate analysis is made 
by H. F. Osburn, an American writer, who enumerates no 
fewer than 24 expressions of heredity. 
Another important point which has been given some 
prominence of late is the view that similar structures often 
arise independently and in diverse ways. Hans Gadow 
has recently brought forward tabulated evidence of this, 
(2) Pr«s. Address, British Association, 1913 
(3) “ Descent of Man,” 2nd Edit., p. 262. 
(4) “ Darwin and Modern Science.” p. 100. 
i5) Jonrn. Nat Sci. Phil., vol. 15, 1912, p. 2H6. 
