Page:Popular Science Monthly Volume 75.djvu/575

Rh almost inevitable collision with these outstretched wing-borders. To lunge at a thing and miss it is inevitably to be carried on, the next instant, close past it. To put it from the insect's point of view, barely to dodge an onrushing foe, is, as we all know, to have him almost inevitably brush against us, to say the least, as his impetus carries him forward. It would be absurd to doubt the very great likelihood of mutilation to the butterfly's wing-borders at such a moment. Again; a bird struggling, against difficulties, to seize such a thing as a zigzagging butterfly, inevitably tries for the mass of the target, the most visible part. Now, although the wings do, certainly, more or less wag the body up and down, nevertheless the body is the axis of the mill-wheel of which the wing-borders are the floats, so that even if the bird tried for the body, unless the attack came exactly from behind, the flapping wings would tend to protect it by constantly getting in the way of the bird's beak, but this would be at the expense of these delicate fabrics, which would smash themselves against it. So much for the immensely greater risk of every sort to this delicate border than to the body itself.

Now as to the supposition that birds prefer to seize this border region, rather than the body. One simple fact suffices to show us that we have not the slightest evidence that they do so. It is this. A butterfly seized by his body can not escape (unless, of course, he chance to be cut nearly through by the beak that seized him) while one seized by the wing-border is no more detained by being thus seized than by receiving at this point any of the merely accidental injuries above referred to. Now if a butterfly seized by the body, is generally eaten, while on the other hand every butterfly injured as to its border, escapes, what possible significance has our finding, as we do, mainly border injuries?

Now, although it seems scarcely necessary to finish the argument, to consider for a moment the supposed selection by the bird, of special points along these borders, the reader has been sufficiently reminded how very far the bird is, in one of these chases, from being in a position to select a point of attack.

We find that the whole subject of animals' coloration has been handled with very loose thinking, as if the old time disrespect of natural history still haunted men's minds and dissuaded them from real study. This cloud that enveloped natural history in former centuries has been steadily thinning, but it is certainly accountable for many loosenesses even up to the present time.

For instance, it is perfectly plain to-day that nature would not ask a coral snake to get along with a costume which, while it often served to warn off his enemies, proved, at other times, a disadvantage to him by identifying him to the animals which he wished to eat. The writings upon these subjects, down to the present day, teem with just this kind