i8 7 8.] 
Doctrine of Development . 
449 
II. THE PROGRESS OF THE DOCTRINE 
OF DEVELOPMENT.* 
S MONG the general public, and even to some extent 
among men of Science who are not biological spe- 
cialists, it is too commonly supposed that Evolu- 
tionism sprang at once into full maturity from the brain of 
Mr. Darwin ; that Darwinism and Evolutionism are con- 
vertible terms ; and that the dodtrine is accepted with but 
little scrutiny by the majority of modern naturalists more 
as an article of faith than a scientific truth. Nothing could 
be farther from the real state of the case. The theories of 
Mr. Darwin are regarded as a mere tentative sketch, to be 
revised, emended, filled in, or even cancelled, as future 
observation and experiment may didtate. To this process 
they are being constantly submitted, and the general result 
may be stated to be that while the belief, or rather the con- 
vidtion, of the truth of Evolution as “ God’s mode of 
Creation ” is gaining ground, the precise agencies by which 
Mr. Darwin supposed such Evolution to be mainly effedted 
are looked upon by many with doubt, or are at least relegated 
to a more subordinate position. 
It is well known that Mr. Darwin, along with many of 
his more immediate followers, ascribes the development of 
species as we actually find them to two causes — both slow, 
gradual, and uniform in their adtion. These are Natural 
Seledtion and Sexual Seledtion, the former an utterly un- 
conscious, but the latter a conscious, agency. To Sexual 
— or, as it has been not unhappily styled, Female — Selec- 
tion he attributes not indeed the origin of any new form of 
life, but the ornamentation, and especially the colours, of 
the higher animals, such as the vertebrates and insedts, and 
especially the generally brighter hues and the decorative ap- 
pendages which characterise the male sex. He argues that 
the females having for ages past given the preference to the 
most beautiful males of their respedtive species, these have 
had a better chance of leaving a numerous offspring than 
their less brilliant rivals, and have transmitted their 
* Tropical Nature and other Essays. By Alfred R. Wallace. (London: 
Macmillan and Co.) 
All the Articles of the Darwin Faith. By the Rev. F. 0. Morris, B.A, 
(London : Moffatt, Page, and Co.) 
Zur Entwickelungs-Geschichte der Menscheit. By L. Geiger. (Stuttgart.) 
VOL. VIII. (N.S.) 2 G 
