38 INSECT ARCHITECTURE. 



usurp the nest which another had formed. A fierce 

 battle was invariably the consequence of this attempt ; 

 for the true mistress would never give place to the 

 intruder. The motive for the injustice and the re- 

 sistance was an indisposition to further labour. The 

 trial of strength was probably, sometimes, of as little 

 use in establishing the right as it is amongst man- 

 kind ; and the proper owner, exhausted by her 

 efforts, had doubtless often to surrender to the dis- 

 honest usurper. 



The account which Reaumur has given of the opera- 

 tions of this class of bees differs considerably from 

 that which we have here detailed ; from the species 

 being different, or from his bees not having been able 

 to procure moist clay. On the contrary, sand was 

 the chief material used by his mason-bees (Megachile 

 muraria) ; which they had the patience to select from 

 the walks of a garden, and knead into a paste or 

 mortar, adapted to their building. They had con- 

 sequently to expend a much greater quantity of 

 saliva, than our bees (Osmia bicornis) which worked 

 with moist clay. Reaumur, indeed, ascertained that 

 every individual grain of sand is moistened previous 

 to its being joined to the pellet, in order to make 

 it adhere more effectually. The tenacity of the 

 mass is besides rendered stronger, he tells us, by 

 adding a proportion of earth or garden mould. In 

 this manner, a ball of mortar is formed, about the 

 size of a small shot, and carried off to the nest. When 

 the structure of this is examined, it has all the appear- 

 ance externally of being composed of earth and small 

 stones or gravel. The ancients, who were by no means 

 accurate naturalists, having observed bees carrying 

 pellets of earth and small stones, supposed that they 

 employed these to add to their weight, in order to 

 steady their flight when impeded by the wind. 



The nests thus constructed appear to have been 



