Page:The Zoologist, 4th series, vol 2 (1898).djvu/501

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ASSIMILATIVE COLOURATION.
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colouration. According to the Biblical narrative, the astute Jacob in his negotiations with Laban increased the number of "ringstraked, speckled, and spotted" cattle by the following ingenious method. He "took him rods of green poplar, and of the hazel and chestnut tree; and pitted white strakes in them, and made the white appear which was in the rods. And he set the rods which he had pitted before the flocks in the gutters in the watering troughs when the flocks came to drink, that they should conceive when they came to drink. And the flocks conceived before the rods, and brought forth cattle ringstraked, speckled, and spotted."[1] This narrative might be used as a theological argument for the theory that wild animals may have acquired their spots and stripes in a similar manner, as the Tiger in his bamboo jungle, &c, and it seems strange in these plentiful days of theory that no clerical evolutionist has advanced such a view. Canon Tristram, however, by his observations in the Sahara, does not advocate this suggestion, for in these desert plains he described sheep in which "Jacob's ringstraked and speckled, dappled with white, and especially light brown predominated."[2]

Another suggestion, to which allusion has already been made, is that of the late Alfred Tylor, who starts with the premiss that it "seems most probable that the fundamental or primitive colouration is arranged in spots,"[3] and that these are capable of being coalesced into bands, stripes, and blotches, and are structural in affinity. "If we take highly decorated species, that is, animals marked by alternate light and dark bands, or spots, such as the Zebra, some Deer, or the carnivora, we find first that the region of the spinal column is marked by a dark stripe; secondly, that the regions of the appendages, or limbs, are differently marked; thirdly, that the flanks are striped or spotted along or between the regions of the lines of the ribs; fourthly, that the shoulder and hip regions are marked by curved lines; fifthly, that the pattern changes, and the direction of the lines, or spots, at the head, neck, and every joint of the limbs; and lastly, that the tips of the ears, nose, tail, and feet, and the eye

  1. Genesis, chap. xxx. verses 37–9. In the following chapter—xxxi. verses 10–13—this is altogether attributed to the favour of the God of Bethel.
  2. 'The Great Sahara,' p. 61.
  3. 'Colouration in Animals and Plants,' p. 23.
Zool. 4th ser. vol. II., November, 1898.
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