XX MASON BEES 277 



name applied to those Hymenoptera that build cells 

 with materials such as we use for our dwellings. 

 It is masonry, but made by a rustic workman, better 

 used to dried clay than to hewn stone. A stranger 

 to scientific classification (and this causes great ob- 

 scurity in some of his memoirs), Reaumur called the 

 worker after the work, and named our builders in 

 dried clay Mason Bees, which paints them exactly. 

 We have two kinds, C. muraria, whose history is 

 admirably given by Reaumur, and C. sicula, which is 

 not special to the land of Etna, as the name 

 suggests, but is found in Greece, Algeria, and the 

 Mediterranean region of France, especially in the 

 department of Vaucluse, where in May it is one of 

 the most common Hymenoptera. The two sexes of 

 C. muraria are so unlike in colouring that a novice 

 observing both coming out of the same nest would 

 take them for strangers to one another. The female 

 is of a splendid velvet black, with dark violet wings ; 

 in the male the black velvet is replaced by a bright 

 iron-red fleece. The second species — a much smaller 

 one — has not this difference of colour, both sexes 

 wearing the same costume — a general mixture of 

 brown, red, and ashy tints. Both begin to build in 

 the beginning of May. The wing-tips, washed with 

 violet on a bronze ground, faintly recall the rich 

 purple of the first species. 



As Reaumur tells us, C. muraria in the northern 

 provinces chooses as the place to fix her nest a wall 

 well exposed to the sun and not plastered, as the 

 plaster might come off and endanger her cells. She 

 only entrusts her constructions to a solid foundation, 

 such as a bare stone. I see that she is equally 



