244 TRANSFORMATIONS OF INSECTS. 



lumps of mud which have been thrown agauist the wall and be- 

 come dried up. They are the constructions of this Hymenoptera^ 

 and when they are examined closely they will be found to be as 

 hard as Roman cement, and to be made up not with mud, but with 

 a mixture of gravel and earth. The lumps are more or less arched, 

 and it is very evident that their rounded state is not a matter of 

 chance. This mixture of earth and gravel sticks to the wall with 

 the greatest tenacity, and the chisel and hammer are requisite to 

 detach it. Now, these ugly and dirty looking masses have been 

 carefully built up, with a wonderful amount of art, by a single 

 Hynienoptera, which has been the architect and workman at the 

 same time. The labours of the Chalicodoma begin in the month 

 of May, and soon after it is born. The female explores and 

 goes over a wall and chooses a particular spot, and having 

 settled that essential point, she goes off to collect building 

 materials, and if followed, will be noticed to alight upon a 

 sandy and gravelly soil. The insect takes up little masses of 

 sand and small stones, of a certain size, with its mandibles, then 

 it disgorges a little saliva and sticks them to some grains of earth, 

 and thus agglutinates the earth and the sand so as to form the 

 mortar which it is going to use in building. When it has worked 

 up a little piece it flies off with its burden, and returns to its 

 wall to fix on this first quantity of cement. The same trouble 

 is taken over and over again, and then, the mass of mortar 

 appearing sufficient to permit other building operations to be 

 commenced, the bee sets to work to mix all the earth, and usually 

 she labours so well as to complete a little cell in one day. This 

 cell is open to a certain extent, and the bee enters it several 

 times to make the inside walls smooth. Then something else 

 besides building has to be done, for the cell has to be victualled, 

 and the CJialicodonia flies off to collect honey and pollen from the 

 flowers. It makes up a sweet cake from them, which will be the 

 future nourishment of its larva;, and then it stufts the cell nearly 

 full of this food, and lays an ^^^ in the midst. The Hynicnop'tcra 

 walls up the cell and sets to work to construct another close to it, 

 then a third, and sometimes as many as twelve or more. These 

 cells are placed rather irregularly, and are not found to be of the 

 same number in every nest. All the cells are built, filled with 



