It is very noteworthy that resemblance in structure is always accompanied by similarity of behaviour—as indeed it is bound to be if any benefit is to accrue to the mimic. Your resemblance to a leaf will deceive no one if you run wildly about, and your imitation of an ant will lack verisimilitude if you adopt a slow and stately method of progression. Ant-like spiders adopt the hurried and apparently undecided gait of their models, and insects which look like sticks, leaves, or inanimate objects all possess the power—and the habit—of remaining for a long time perfectly motionless. CHAPTER IX WOLF-SPIDERS Of the groups of wandering spiders, which spin no snare but trust to speed and agility for their food, the Lycosidae or wolf-spiders supply the best subjects for study. To begin with, they are very numerous at certain times of the year, some species absolutely swarming in woods during May and June among the leaves which fell in the previous autumn. During the summer months they are still in evidence, but as winter approaches they rapidly disappear. The swift motion and predaceous habits have earned them the name of wolf-spiders, but though they sometimes occur in incredible numbers so that it seems impossible to avoid treading upon them, they do not hunt in packs; each one is entirely concerned with his own individual quarry. They are moderate-sized or large spiders—commonly about half an inch long in this country though there are exotic species which attain an inch and a quarter—and in build they are very unlike the garden-spider, being elongate, and with the abdomen nothing like so globular. Their habits vary considerably. One genus, appropriately named _Pirata_, is semi-aquatic, living at the margins of rivers and ponds, and able to run on the surface of the water, but most of the Lycosidae prefer dry land—the dryer the better. Heaths, sandhills, bare and stony stretches of soil, even deserts, are fertile in examples of this group. Most of the smaller species love the sunlight, and it is often noticeable on a bright day, when the ground seems to be alive with wolf-spiders, that a chance cloud obscuring the sun will cause them to disappear as if by magic. Some of the small Lycosids seem to be absolute wanderers, having no home at all, but spending the night under a stone or any casual shelter, while others dig a more or less temporary hole in the ground into which they carry their captured prey, and in which they take refuge on the appearance of an enemy. The large wolf-spiders have permanent burrows from which they do not wander far and in the mouths of which they spend most of their time, on the look out for passing insects.