ASSIMILATIVE COLOURATION. 473 
were a genius loci, whose subtle and pervading essence spread 
itself around, penetrating and impregnating the denizens of the 
place with its facies,—possibly only affecting some, the conditions 
of whose entry on existence render them more liable to receive 
its impression than others; more probably affecting all, some 
more and some less,” &c.* It may, however, be suggested that 
this adaptive colouration was due to an assimilative process in 
early times,+ and that the ‘‘ genius loct”’ is a pseudonym of tbat 
operation. It is at least probable that where we have protective 
resemblance in a unicolorous condition, it is a survival of 
original assimilative colouration, and is not a direct product of 
“natural selection”; but is ratified and perpetuated by that 
agency as agreeing altogether with its conditions. Unchanged it 
has survived as the fittest.{ It must have been in the original 
head-quarters or centre of evolution before migration took place, 
and a uni- or concolorous hue prevailed. Such a centre for 
Anthropoids, paleontology proves to have once existed in India. 
In the words of Mr. Lydekker :—‘‘ We have decisive proof that 
at a former epoch of the earth’s history such an assembly of 
Primates was gathered together on the plains of India at a time 
when the Himalaya did not exist as has been seen nowhere else 
beyond the walls of a menagerie. Side by side with Langurs and 
Macaques closely resembling those now found in that region 
were Chimpanzees and Baboons as nearly related to those of 
modern. Africa, whilst the extinct Indian Orang recalls the exist- 
ing species of Borneo and Sumatra. India, therefore, in the 
Pliocene period, seems to have been the central point whence the 
main groups of Old World Primates dispersed themselves to their 
far distant homes.” 
* * Discuises in Nature,” vide ‘Edinburgh New Philosoph. Journ.,’ 
January, 1860. 
+ Eimer proposes a theory of colour-photography: ‘‘ The colours of the 
environment of an animal may be reflected in the colours of its skin” 
(‘Organic Evolution,’ Eng. transl. p. 145). 
| A different argument, propounded on somewhat similar grounds, was 
advanced by Agassiz in his “ Natural Relations between Animals and the 
Elements in which they live,” to prove that marine animals were less 
specialised in structure than those inhabiting the land areas (vide Silliman’s 
‘Amer, Journ. Sci. and Arts,’ May, 1850). 
