i88i.] 
549 
Analyses of Books. 
during the pupa state, and when the insedt is as far withdrawn 
as possible from external influences. Still he thinks that in the 
two groups the phenomena do not originate in distincft proximate 
causes, and that among vertebrates, as among insedts, “ we shall 
be forced to discard the idea of diredt physical causation.” This 
is substantially an admission that the laws of the produdtion and 
distribution of colour in animals are beyond the reach of man’s 
intelligence. 
He points out several objections to the theory of the Rev. H. 
Higgins, who maintains that the dark spots are chiefly seated on 
the wings in consequence of the greater facilities there for the 
deposition of colouring-matter. Mr. Scudder shows that, on the 
contrary, in the body of the wing the coloured spots are invariably 
placed in the interspaces between the longitudinal veins. 
The author’s own hypothesis is that “ the wings of butterflies 
first showed signs of divergence from uniformity by a deepening 
of the colour next the outer margin, which thereafter became 
separated into distincft transverse bands : these bands in breaking 
up gave rise to dark-veined or to spotted wings, which served as 
the basis for all the variegated patterns of the present day, in- 
cluding ocelli, which are only specialised forms of simple inter- 
spacial spots.” 
It has always seemed to us that the intensification of colour 
along the margins of the wings, or of certain portions of the 
wings, is connected with capillary attraction. With the author’s 
observation that “ to a certain extent there is a polar distribution 
of markings ” we fully agree. Mr. Scudder does not appear to 
lay much emphasis upon “ sexual selection ” as a cause of the 
varied tints and patterns in butterflies. Nor is he an unlimited 
believer in the doctrine of protective colouration. He asks, 
“ Can such a play of plan in ornamentation be explained as 
purely for the purposes of the ephemeral creature itself ? If it 
cannot, — if, for instance, it is of no advantage to the butterfly 
that its second brilliant ocellus should occur in the area of the 
first rather than of the second vein, — then it cannot have arisen 
through natural selection without the guidance of a higher law, 
which has other ends for beauty than the mere survival of the 
creature possessing it.” 
In the chapter on “Ancestry and Classification ” we find the 
following significant passage : — “ That the groupings and rela- 
tions of structure among animals are clear to the human mind, 
— that they present an orderly arrangement and a harmonious 
inter-combination which appeals to his reason, — is sufficient proof 
that natural selection, in all its wondrous and pervading power, 
acfts under law, a law of Evolution which is no slave to the forces 
of Nature, but brings them into subservience to its ends ; a law 
which is working out the plans of a Supreme Intelligence by 
ways which man may apprehend, but has not yet comprehended.” 
We regret that we must here bring our survey of this work to 
