to the Spotted Deer, says, "unless it moves, few beasts are more difficult to see; the colour of the skin harmonizes with the dead leaves and grass, while the white spots are indistinguishable from the little flecks of light caused by the sunshine passing through the leafy branches."[1] These observations have the great merit of being neither the result of preconceived opinion, nor the effort to support a theory. Mr. Galton's journey was made during the years 1850–2, before the advent of that epoch-making work the 'Origin of Species,' which at once rivetted attention on all these phenomena. General Douglas Hamilton simply recorded the impressions of a sportsman with thirty-five years' experience in India. Such testimony cannot be gainsaid, and though numerous other illustrations could readily be compiled, and from the pens of capable observers, those here given will suffice as regards the standard of competence and accuracy. On the other hand, I was surprised, in reading the 'Travels and Adventures in South East Africa' of that celebrated and experienced hunter, Mr. P.C. Selous, that he seemed to have no similar observations to record.
In reference to the above instances of spots and stripes affording concealment, the explanation of "active mimicry," as I hope to advocate subsequently, might be applied; but then it must be remembered that the same phenomenon is found in other animals who live under very different conditions. Thus the Zebra Shark (Stegostoma tigrinum) is marked with black or brown transverse bars or round spots. Again, in Australia, according to Prof. Strong, the Rabbit is not only often parti-coloured, but numerous instances occur not only of white and black Rabbits, but of Rabbits "with beautifully striped skins."[2]
The origin of spots and stripes is shrouded in obscurity. In domesticated animals, such as Dogs, Cats, cattle, and Horses, unsymmetrical markings constantly occur. According to Mr. Wallace, "Such markings never occur in wild races, or if they occur in individual cases they never increase; and I have given
- ↑ 'Roy. Nat. Hist.,' vol. ii. p. 855.—Livingstone seems inclined to the opinion that such animals take refuge in the forest to escape from the hunters: " But here, where they are killed by the arrows of the Balonda, they select for safety the densest forest, where the arrow cannot be easily shot" ('Missionary Travels and Researches in South Africa,' p. 280).
- ↑ 'Zoologist,' 3rd ser., vol. xviii. p. 406.
