depends, would scarcely be suspended for a longer period than necessary for sexual union. Spiders frequently eat one another, and such an occurrence after pairing is only curious if considered apart from their habits. When the sexual desire is satisfied, their actions would again be directed by the dominant instinct of destruction. It is to be noticed that the attack, when made by a female, often immediately follows the sexual union, while in the case where males assume the aggressive it takes place some time afterwards. Mr. Campbell explains this by the supposition that the action of the female, when satiated, would be precipitated by the threatened and unacceptable continued application of the hard, spiny palpus, while the more lasting desire of the male would have to subside before he became directed by another instinct. By that time, other attractions, if not his wandering disposition, would take him away from the web. The fact that male Spiders are comparatively rare is perhaps explained by the fact that they are very short-lived; they probably die soon after pairing—even if they are not eaten! The snares they spin, it is to be noted, are very imperfect, though curiously enough, when young they make perfect snares on a small scale. It will have been noticed, in the course of the foregoing descriptions, that Spiders display a more or less conspicuous wariness, a cool, deliberate “counting on the cost” in their matrimonial ventures that is often wanting in such matters in the human race. But, then, the risks involved are more patent, more imminent. Mr. Campbell comments on this intelligent behaviour in the case of the Cellar Spider, remarking that they measure “each other’s strength when on the same web by the tension and motion of the threads.” A word as to the Scorpions. These creatures are near relations of the Spiders, and in many things resemble them, notably in regard to their ferocity. One does not meet here, however, with the same disparity in size between the sexes, nor are vivid colours ever developed. This, according to some, would be accounted for by the fact that though these creatures possess numerous eyes they are practically blind, and depend for their information as to what is going on around them by their sense of touch, which is excessively delicate. They are morose in disposition and always solitary. It has been said that if two are found under the same stone—a favourite lurking-place—one is engaged in eating the other! Nevertheless, they are of abstemious habits, for the naturalist Fabre found that from October to March they last, though throughout this time they remain alert, and always ready to resent disturbance. In April they exhibit more activity, though even then they eat but little. But now they begin to wander in search of mates.