described inhabits Corsica, Sardinia, and the parts of Italy near Mentone. Its nest, usually built in the light red clay of the region, is a beautiful construction, from four to eight inches deep, and about five eighths of an inch in diameter. Like the others, these nests are usually grouped in considerable numbers, very near to one another; sometimes, indeed, they are contiguous. The first admirers of the art of these creatures, the "pioneer ctenizas"—the Italian Pietro Rossi, and the Frenchman Victor Audouin—were struck with this association, so like that of villages; for we do not usually think of spiders without conceiving them as solitary and isolated. But it is evident that these trap-door spiders do not hold that antipathy toward their fellows by race which is the rule in the Arachnidan world. While everywhere else, with this strange race, the association of males and females is only for an instant, and is accomplished by a surprise, the manners of the ctenizas are more gentle and like those of birds. The chief difference is that, while the bird builds a nest for its family, the cteniza has a permanent home in which to accommodate its offspring. The ctenizas behave as if they knew what was to occur. At the time of reproduction, a male is admitted to the residence of the female, and becomes a guest there. The eggs having been laid, the couple appear to watch together over the deposit with the best understanding, and an equal solicitude. But when the young have become large enough, like young birds, they leave the nest and assume their independence without any further concern for parental cares, and the father and mother separate, to resume the freedom of isolation. And when we observe a male in the cell of a female, we are inclined to think that many doors are open to him; for females are numerous and males are rare.
Mr. Traherne Moggridge undertook to obtain a deeper view of the life-secrets of the mason or trap-door spiders. As they work at night, it was not easy to surprise them when active in their labors; but much may be accomplished in the way of discovery by the exercise of patience and sagacity. Mr. Moggridge found it a good plan to follow the spider in building a new abode when its old one had been demolished. It executes its task speedily, without neglecting any detail, as if in obedience to a perfect method. The favorite places are the slopes of terraces and the banks of rivers; choosing a time, if it can, when the ground is moist, it clears away the earth with its claw-rake, and marks out the cylindrical hole. If there are any places in the walls that lack cohesion and where a slide may be anticipated, the animal, as if it were a graduate from a school of engineers, consolidates the parts with silk and weaves in successive layers the pretty satiny texture with which its house is to be adorned. It pursues its task in this way till the determined depth is reached. The tube having been con-
