Page:Popular Science Monthly Volume 38.djvu/203

Rh by Moggridge. Here we have simply a dropping away of the turret of Dolichoscaptus, and the use of the burrow independently of the same, but with the trap-door retained. In the species studied by Moggridge a single burrow is the ordinary rule; but there are many variations, some of which are manifestly characteristic of species, and others which are probably occasional and accidental. A variation described by Mr. Simon is shown at Fig. 5, the nest of Stothis astuta, which inhabits the forest of Cartuche, near Carácas, South America. The drawing shows a section of the burrow, indicating the curved course, and also the two wafer-like trap-doors habitually placed at either end. That this peculiar industry is defensive is probable, for we can readily imagine the spider disappearing within its den at one door, and, if its pursuer should succeed in entering the same, escaping at the other. We might, without much stress of imagination, carry the conception a little further, and suppose, again, the enemy making its exit from one door and the spider again descending into its burrow by the other. This game of bopeep might evidently be played to the great advantage of the trap-door spider, and manifest disconcerting of its enemy.

Simon gives an interesting example of the ability of a spider of this species to change its habit and adapt its industry to unexpected surroundings. The species commonly seeks dark and damp localities, and digs in vegetable earth a burrow not very deep. The nest was begun underneath a stone in soil which was so rocky as to be impenetrable. Not wishing to change its site, and