On the open downs, and when the sun is shining, the air is filled with the hum of chirping insect life from the many species of grasshoppers, crickets and small locusts which cover the ground. Every step among the long dry grass disturbs a score of these insects, which leap in all directions from one’s path as we proceed, sometimes dashing on one’s face with a smart blow. The majority of these are of various shades of brown and green, and some of the larger species of grasshopper are remarkable for their protective colouring. Here is one whose legs and wings are exactly like dry grass; the body is like a broad blade of some green plant, the antennæ are two little tufts, like yellow grass, and the eyes are just like two small brown seeds. But, curiously enough, when it flies, a pair of bright scarlet wings make its flight very conspicuous. You pursue it, to catch such a brightly coloured insect, when it settles, and lo! it has vanished, only something resembling green or dry grass remains, which it requires sharp eyes to distinguish from the surrounding herbage. Other grasshoppers are entirely like green grass blades and stalks, and others again resemble, equally closely, dried grass; and unless the insects move under one’s eyes it is almost impossible to detect them. One is puzzled to guess where the vital organs can be placed in such dry-looking little sticks. There is one species of mantis also, which, in the shape and colour of its wings, legs, antennæ and body, presents as close a resemblance to its environment as do the grasshoppers. Their curious heads, however, which turn round and look at one in quite an uncanny manner, and their formidably serrated fore legs or arms, put up in mock pious fashion, give them a distinctly different appearance from the other insects. In the dry and cooler season on almost every square foot of ground is a large brown caterpillar, often many of them close together, feeding on the young blades of grass. [Sidenote: PROTECTIVE RESEMBLANCE]