220 TRANSFORMATIONS OF INSECTS. 
long waists and very arched mandibles, without teeth on their 
internal edge. The insects are black, with yellow marks upon 
them. They are perfect 
masons, and work in a most intelligent 
and persevering manner. A species common in Central France 
Pelopeus spirifex AND ITS NEST. 
(Pelopeus spirifex) builds its nest in walls, in corners of 
buildings, and sometimes within barns and_ houses, but almost 
always at the height of several yards from the ground. The 
insect is very slender, and does not seem fitted to carry burdens, 
but nevertheless it seeks clayey spots, and beats up small portions 
