INSECT WAYS AND MEANS.
IV.—HOW INSECTS SEE.
Of the five senses, sight is to mankind undoubtedly the most precious. The changes of the seasons, the beauty of scenery, sunset and sunrise, the wonders of nature, and the triumphs of art are only to be appreciated through the eyes, which have aptly been described as the 'windows of the soul.' Yet there are many who pass through life without even realising what we may call the 'gilding' of the world—the delights of colour. Quite a large number of people have no colour-sense, and are unable to tell red, for instance, from green. The writer knows an eminent botanist who is unable to tell the colours of the flowers he so loves to study!
Fig. 1.—Head of Insect with eyes at side (greatly magnified).
How is it with the little people of the insect world in this matter? Their eyes are constructed on an entirely different plan from ours. What sort of a world is it that they look on? Taken as a whole, it would seem that the insect inhabitants of our world see but very little of it; they perceive it rather through the sense of smell. Only a very few insects, such as dragon-flies, for example, see well, and even their length of sight probably does not exceed six feet or so. They are a near-sighted race. Moreover, they see moving objects more easily than stationary ones.