SPIDERS. 361 



form of a tube, about one inch in diameter, between 

 six and seven inches long, and slightly bent towards 

 the lower extremity — appearing to have been mined 

 into the clay rather than built. The interior of the 

 tube is lined with a uniform tapestry of silken web, 

 of an orange-white colour, with a texture interme- 

 diate between India paper and very fine glove leather. 

 But the most wonderful part of this nest is its en- 

 trance, which we look upon as the perfection of insect 

 architecture. A circular door, about the size of a 

 crown-piece, slightly concave on the outside and 

 convex within, is formed of more than a dozen layers 

 of the same web which lines the interior, closely laid 

 upon one another, and shaped so that the inner 

 layers are the broadest, the outer being gradually less 

 in diameter, except towards the hinge, which is about 

 an inch long ; and in consequence of all the layers 

 being united there, and prolonged into the tube, it 

 becomes the thickest and strongest part of the struc- 

 ture. The elasticity of the materials, also, gives to 

 this hinge the remarkable peculiarity of acting like a 

 spring, and shutting the door of the nest spontane- 

 ously. It is, besides, made to fit so accurately to the 

 aperture, which is composed of similar concentric 

 layers of web, that it is almost impossible to distin- 

 guish the joining by the most careful inspection. To 

 gratify curiosity, the door has been opened and shut 

 hundreds of times, without in the least destroying 

 the power of the spring. When the door is shut, it 

 resembles some of the lichens (Lecidea), or the 

 leathery fungi, such as Polyporus versicolor, (Mi- 

 cheli,) or, nearer still, the upper valve of a young 

 oyster shell. The door of the nest, the only part seen 

 above ground, being of a blackish-brown colour, it 

 must be very difficult to discover.* 



Another mason-spider (Myyale camentaria, Lath.), 

 * J.'lt. 



