Page:The Zoologist, 4th series, vol 3 (1899).djvu/573

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MIMICRY.
543

ceeding, as far as intention is exhibited, though appertaining more to what is understood by "aggressive mimicry," is to be found in the account of the habits of the Cassowary (Casuarius bennetti), given by Mr. Wilfred Powell as observed in the island of New Britain:—"I saw a Morroop (Cassowary) come down to the water's edge, and stand for some minutes, apparently watching the water carefully; it then stepped into the river, where the water was about three feet deep, and, partially squatting down, spread its wings out, submerging them, the feathers being spread and ruffled. The bird remained perfectly motionless; I also noticed that the eyes were closed, as if asleep. It remained in this position for fully a quarter of an hour, when, suddenly closing its wings and straightening its feathers, it stepped out on the bank, where, shaking itself several times, a quantity of small fishes fell from under the wings and from amidst the feathers, which were immediately picked up and swallowed. The fishes had evidently mistaken the feathers for a description of weed that grows in the water along the banks of the rivers in this island, and very much resembles the feathers of the Cassowary, and in which the smaller fish hide to avoid the larger ones that prey on them."[1] The Ruffed or Birch Partridge in Canada has been described by Dr. Leith Adams as flying to a tree to escape danger, where "their statue-like posture, with neck outstretched, and their motionless position on the moss-clad spruce-bough, render it extremely difficult to recognize them." So close is this active mimicry carried out that it is sometimes only by the barking of Dogs that the sportsman is aware of the close proximity of the birds. In the words of Dr. Adams, describing an actual experience, "In vain we looked, for no Partridge was to be seen; still the Dog barked, and began to bite and tear off the bark, when at length three birds were discovered standing motionless on the moss-covered boughs, and within a few yards of us."[2] Even more forcibly Mr. Anthony, of San Diego, California, describes the active mimicry of the "Long-eared Owls," who can assume a "rigid, stick-like position" to the surrounding shrubs and branches. "To escape notice—so great is their faith

  1. 'Wanderings in a Wild Country,' pp. 271–2; and 'Proc. Zool. Soc.' June 15th, 1880.
  2. 'Field and Forest Rambles,' pp. 175 and 176.