Page:The Zoologist, 4th series, vol 3 (1899).djvu/378

350 If there is truth in this view, it should be emphasized by the fact that animals of great fecundity, as a rule, possess little protective disguise in colouration or markings, and this, in a great measure, appears to be the case, despite the somewhat contrary evidence which tends to be deducible from the colours of many flat-fishes. Even in this case we must remember that other senses besides those of sight may be used to discover a semi-concealed prey. The extreme hardihood of certain animals after injury is also an agency in "survival." Prof. Mcintosh relates that "a full-grown female Picked-Dogfish was captured in the stake-nets for Salmon some years ago with its stomach distended with food. In dissecting the apparently dead animal in the laboratory the heart pulsated actively, though it and the pericardium were covered with old and recent lymph, caused by the irritation of a large Cod-hook, the point of which projected into the pericardium, and against which the heart seemed to impinge during contraction. An Eel will live for a year or two with a hook projecting through the gut into the abdomen, and the glutinous Hag (Myxine) is also hardy under similar circumstances." In so often seeking for the explanation of animal survival by mimetic or assimilative disguises, we are probably endeavouring to open too many locks with one key.

Colour alone may prove a false analogy to protection. Mr. Beddard has well observed:—"The bluish and white colour of many Gulls is generally allowed to be of protective value; in any case, they are not unlike their usual surroundings. For three years several of the common species of Gulls have a brownish speckled plumage, which is totally unlike that of the old bird; if one colour is advantageous, the other must be the reverse; and three years is either a considerable period, or not long enough." Another illustration is from a writer who, recording his views as to protective resemblances in South America, describes the wellknown butterfly, Ageronia feronica, which rests with its wings expanded horizontally. When seen on the "grey lichens or bark of the tree-trunk," it is "then so like in colour and markings to the surface on which it rests that it is practically invisible