1")2 LETTERS ON ENTOMOLOGY. 
lives in the South American woods, and was scid 
to catch even small birds, but this has been 
denied by Langsdorf. 
One spider actually makes a room, with a door 
turning on a hinge, however surprising it may 
appear to you. This room is a subterraneous 
gallery, upwards of two feet in length, and half 
an inch broad. This tunnel, which is very large 
compared to the insect, is dug by her strong 
jaws in a steep bank of clay. The next operation 
is to line the whole with a web of fine silk, which 
serves the double purpose of preventing the earth 
from falling in, and by its connexion with the 
orifice, giving notice of what is passing. The 
door is formed of several coats of dried earth, 
fastened together with silk : when finished, its 
outline is as perfectly round as if traced with 
compasses ; the inside is convex and smooth, the 
outside flat and rough, and so like the surround- 
ing earth as not to be distinguishable. This 
door the ingenious spider fixes at the entrance 
by a hinge of silk, which allows it to be opened 
and shut with ease ; and as if acquainted with 
the laws of gravity, she invariably fixes the hinge 
at the highest side of the opening, which you 
may remember is sloping, so that the door, when 
pushed up, shuts again with its own weight. 
