XX MASON BEES 275 



polygons ; trapezes and triangles might be joined 

 at will. Wide distances suggested plenty of elbow 

 room, and there was even an ancient building, once 

 a dovecote, which lent its vertical lines to the ser- 

 vice of the graphometer. 



Now from the very first a suspicious something 

 caught my attention. If a scholar were sent to 

 plant a distant stake I saw him frequently pause, 

 stoop, rise, seek about, and stoop again, forgetful of 

 straight line and of signals. Another, whose work 

 it was to pick up pegs, forgot the iron spike and 

 took a pebble instead ; and a third, deaf to the 

 measurements of the angle, crumbled up a clod. 

 The greater number were caught licking a bit of 

 straw, and polygons stood still, and diagonals came 

 to grief. What could be the mystery ? I inquired, 

 and all was explained. Searcher and observer born, 

 the scholar was well aware of what the master was 

 ignorant of — namely, that a great black bee makes 

 earthen nests on the pebbles of the harmas, and 

 that in these nests there is honey. My surveyors 

 were opening and emptying the cells with a straw. 

 I was instructed in the proper method. The honey, 

 though somewhat strong-flavoured, is very accept- 

 able ; I in turn acquired a taste for it, and joined 

 the nest-hunters. Later, the polygon was resumed. 

 Thus it was that for the first time I saw Reaumur's 

 Mason Bee, knowing neither its history nor its 

 historian. 



This splendid Hymenopteron, with its dark violet 

 wings and costume of black velvet, its rustic construc- 

 tions on the sun-warmed pebbles among the thyme, 

 its honey, which brought diversion from the severities 



