The most powerful Spider in my district, the Black-bellied Tarantula, will presently give us something to think about, in this connection.  It is not my business to discuss a medical point, I interest myself especially in matters of instinct; but, as the poison-fangs play a leading part in the huntress’ manoeuvres of war, I shall speak of their effects by the way.  The habits of the Tarantula, her ambushes, her artifices, her methods of killing her prey:  these constitute my subject.  I will preface it with an account by Leon Dufour, {2} one of those accounts in which I used to delight and which did much to bring me into closer touch with the insect.  The Wizard of the Landes tells us of the ordinary Tarantula, that of the Calabrias, observed by him in Spain: 

’Lycosa tarantula by preference inhabits open places, dry, arid, uncultivated places, exposed to the sun.  She lives generally—­at least when full-grown—­in underground passages, regular burrows, which she digs for herself.  These burrows are cylindrical; they are often an inch in diameter and run into the ground to a depth of more than a foot; but they are not perpendicular.  The inhabitant of this gut proves that she is at the same time a skilful hunter and an able engineer.  It was a question for her not only of constructing a deep retreat that could hide her from the pursuit of her foes:  she also had to set up her observatory whence to watch for her prey and dart out upon it.  The Tarantula provides for every contingency:  the underground passage, in fact, begins by being vertical, but, at four or five inches from the surface, it bends at an obtuse angle, forms a horizontal turning and then becomes perpendicular once more.  It is at the elbow of this tunnel that the Tarantula posts herself as a vigilant sentry and does not for a moment lose sight of the door of her dwelling; it was there that, at the period when I was hunting her, I used to see those eyes gleaming like diamonds, bright as a cat’s eyes in the dark.

’The outer orifice of the Tarantula’s burrow is usually surmounted by a shaft constructed throughout by herself.  It is a genuine work of architecture, standing as much as an inch above the ground and sometimes two inches in diameter, so that it is wider than the burrow itself.  This last circumstance, which seems to have been calculated by the industrious Spider, lends itself admirably to the necessary extension of the legs at the moment when the prey is to be seized.  The shaft is composed mainly of bits of dry wood joined by a little clay and so artistically laid, one above the other, that they form the scaffolding of a straight column, the inside of which is a hollow cylinder.  The solidity of this tubular building, of this outwork, is ensured above all by the fact that it is lined, upholstered within, with a texture woven by the Lycosa’s {3} spinnerets and continued throughout the interior of the burrow.  It is easy to imagine