266 HABITATIONS OF INSECTS. 



above. You doubtless suppose that in saying door, I am speaking meta- 

 phorically. It could never enter into your conception that any animal, 

 much less an insect, could construct anything really deserving of that name 

 anything like our doors, turning upon a hinge, and accurately fitted to 

 the frame of the opening which it is intended to close. Yet such a door, 

 incredible as it may seem, is actually framed by this spider. It does not, 

 indeed, like us, compose it of wood, but of several coats of dried earth 

 fastened to each other with silk. When finished, its outline is as perfectly 

 circular as if traced with compasses ; the inferior surface is convex and 

 smooth, the superior flat and rough, and so like the adjoining earth as not 

 to be distinguishable from it. This door the ingenious artist fixes to the 

 entrance of her gallery by a hinge of silk, which plays with the greatest 

 freedom, and allows it to be opened and shut with ease ; and, as if ac- 

 quainted with the laws of gravity, she invariably fixes the hinge at the 

 highest side of the opening, so that the door when pushed up shuts again 

 by its own weight. She has not less sagaciously left a little edge or groove 

 just within the entrance, upon which the door closes, and to which it fits 

 with such precision that it seems to make but one surface with it. Such 

 is the astonishing structure of this little animal's abode ; nor is its defence 

 of its subterraneous cavern less surprising. If an observer adroitly insi- 

 nuates the point of a pin under the edge of the door, and elevates it a little, 

 he immediately perceives a very strong resistance. What is its cause ? 

 The spider, warned by the vibrations of the threads which extend from the 

 door to the bottom of her gallery, runs with all speed to the door, fastens 

 its legs to it on one side, and on the other to the walls, and, turning upon 

 its back, pulls with all its might. Thus the door is alternately shut or 

 opened, as the exertion of the observer or of the spider prevail. It is easy 

 to guess which will in the end conquer ; and the spider, when it finds all 

 resistance ineffectual, betakes itself to flight, and retreats. If, to make a 

 further experiment, the observer fastens down the door so that it cannot 

 be forced open, the next morning he will find a new entrance, with a new 

 door formed at a small distance ; or, if he take the door entirely away, 

 another will be constructed in less than twelve hours. 



The habitation thus singularly formed and defended is not at all used as 

 a snare, but merely as a safe abode for the spider, which hunts its prey at 

 night only ; and, when caught, devours it in security at the bottom of its 

 den, which is generally strewed with the remains of coleopterous insects. 1 

 From some curious observations of M. Dorthes on this species in the 

 second volume of the Linnean Transactions, it appears that both the male 

 and female spider, and as many as thirty young ones, occasionally inhabit 

 one of these galleries. Mygale Sauvagesii of Rossi (M.fodiens Walck.), 

 which is a distinct species found in Corsica, forms a similar habitation, of 

 which M. Audouin has given us an interesting description. 2 



The galleries just described are the work of European spiders ; but 

 similar ones are fabricated by Actinopus nidulans, an inhabitant of the West 

 India islands, as well as by many other tropical species. I have seen one 

 of these, which had been dug out of the earth, in the cabinet of Thomas 

 Hall, Esq., F.L.S., that was nearly a foot in length, and above an inch in 



* Sauvages, Hist, de VAcad. des Sc. de Paris, 1758, p. 26. 

 a Audouin in Ann. Soc. Ent. de France, ii. 69. 



