384 THE ZOOLOGIST. 
must have developed ; and this we may imagine to have been of 
an assimilative hue, for, as Poulton has remarked, “ali animal 
colour must have been originally non-significant; for, although 
selective agencies have found manifold uses for colour, this fact 
can never have accounted for its first appearance.’* We may 
think with Grant Allen, who asserts of the unbroken green hue 
which was the dominant feature of the flowerless carboniferous 
era: “ EKqually unvaried, no doubt, was the hue of the articulate 
creatures which fed amid those green jungles of tangled fern and 
club-moss. A few scorpion-like insects, an occasional cockroach, 
beetle, or other uncanny creeping thing may still be detected in 
the débris of a forgotten world; but no trace of a bee, a moth, 
or a joyous butterfly can be discovered in these earliest ages of 
animal life.” + Many phases of plant-life can only be understood 
by a knowledge of past geological conditions. Mr. Harshberger, 
of Pennsylvania, has recently discussed the origin of the vernal 
flora of his own land, and has apparently shown that the flowering 
time of many plants and trees is a direct product of heredity 
from the glacial period.{ It therefore seems possible that 
assimilative colouration may have been a first and very general 
consequent in animal development; that such a view is suggested 
by many facts; and that the subsequent protective resemblance 
acquired by numerous living creatures through the process of 
natural selection, when life had advanced to the competitive 
stage, is far too frequently used as an explanation for whole series 
of uniform phenomena in colouration, which have probably sur- 
vived unaltered from remote antiquity, and which by their very 
essence were “ outside the law’’§ of natural selection, or un- 
* ©Colours of Animals,’ p. 13. 
+ ‘The Colour-Sense,’ p. 38. 
t ‘Science,’ new ser. vol. i. pp. 92-8. 
§ The reader will readily apprehend that by the term “law” we mean 
observed, constant, sequence in phenomena. As Prof. Huxley remarks :— 
“The habitual use of the word ‘law,’ in the sense of an active thing, is 
almost a mark of pseudo-science; it characterizes the writings of those who 
have appropriated the forms of science without knowing anything of its 
substance” (‘Collected Essays,’ vol. v. p. 79). And again:—‘‘We have 
succeeded in finding out the rules of action of a little bit of the universe; we 
call these rules ‘laws of nature,’ not because anybody knows whether they 
bind nature or not, but because we find it is obligatory on us to take them 
