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.
Let us first catch one of the small wolf-spiders and examine it. This is not a very simple operation with creatures which can run so swiftly, but after a few attempts we induce a specimen to run up into a glass tube held in the line of its course. We see it to be a long-bodied spider thickly beset with hairs which entirely hide the integument of the abdomen. Its general hue will probably be a dark grey, and its abdomen will be decorated by a more or less distinct pattern due, not as in the garden spider to pigments in the skin, but to the coloration of the hairs. But look particularly at its eyes. A pocket-lens will suffice to reveal that two of them are much larger and much more business-like in appearance than anything Epeira had to show. These are directed forwards, being placed at the upper angles of the perpendicular front face, so to speak, of the animal. Below them, just above the jaws, are four small eyes in a transverse row, and behind them at some distance, on the upper surface of the cephalothorax, are yet another pair of moderate size. In some groups of spiders the eyes are not only small but have an indefinite, dull, ineffectual appearance; here they are clear-cut, glossy and convex; sight apparently counts for something in the case of the Lycosidae. And this is what we should expect. A sedentary spider is informed of the whereabouts of its prey by the sense of touch, through the trembling of the web, but a wolf-spider spins no web and is dependent on the keenness of its vision.
There is a very prettily marked English Lycosid which is often found on sandhills, in situations particularly convenient for observation. Its name is Lycosa picta, and it is incidentally interesting as affording a good example of protective coloration, for the sandhill variety is light-coloured and very inconspicuous when stationary on the sand, while an inland variety not uncommon on the dark soil of heaths is of a much darker hue. Carefully scrutinising the firmer sand of the dunes on a sunny June day, I detect a number of small holes—the burrows of a colony of these spiders—and approaching cautiously I establish myself at full length at a distance of a yard or so on the side away from the sun, in such an attitude that I can observe closely for a considerable time without too much discomfort. The minutes pass and nothing happens, but I know that the cardinal virtue of the naturalist is patience, and I wait. Presently the dark circle of one of the burrows is obliterated—it is filled by the sand-coloured head of the spider, coming up to prospect. Other heads appear, and soon one spider, bolder than the rest, emerges bodily, and remains for a minute motionless, on the qui vive. Finding no cause for alarm, it presently begins moving about stealthily, and before long several members of the colony are busily exploring the neighbourhood. A cloud passes over the sun and all quickly disappear into their holes, but this time without alarm, for they come forth unhesitatingly when the sun shines again.
It is a fascinating sight to observe these little creatures pursuing their operations in absolute silence under my very eyes. A few stealthy steps are taken, the body being so moved that the battery of eyes is brought to bear upon different points of the compass; a short quick run ensues, followed by more cautious movements. I am not fortunate enough to see the actual running down of a quarry, but in time I note one of the colony bringing home an insect in its jaws. So absorbed am I that I fairly jump when a horrified human voice close at hand observes “He’s in a fit”! I have excited the solicitude of a girls’ school which has approached noiselessly over the sand on their afternoon promenade, and stands gazing at me with as much fascination as I at the spiders. I hasten to reassure them, but the spell is broken, and the séance is at an end. Not a spider is visible.
But I can still do one thing. Here is a good opportunity of finding out something about the burrows of these spiders. In turf the investigation would be difficult, but it is easy to operate in the tolerably firm sand where the colony has established itself.
I insert a straw into one of the burrows as a guide to the exploration, and with a knife carefully begin to remove the sand immediately round it. It is lined, I find, by a very delicate and slight coating of silk, no more than sufficient to keep the sand particles of its walls from falling down into the tube. I go down for an inch and a half or so and find that the tube ends blindly in a sort of silk-lined pocket, but no spider is there! This is mysterious, for I am pretty sure that my spiders are at home.
I go to work upon another burrow, but this time in a different way, digging it out bodily with its surrounding sand, and placing it on a sheet of paper, with which I am luckily provided, for a detailed examination. I can now approach it from the side, and by carefully removing the sand, lay bare the whole silken tube. As before there is a straight perpendicular burrow, ending blindly, and uninhabited, but at a point at about half-way down the tube I find a branch bending upward, so that the whole tunnel is Y shaped, and at the blind end of this branch I find the spider.
This observation suggests that the tunnels of some of our English wolf-spiders may be more complex than was imagined. At present nothing is known of their nature in the case of other species.