UPHOLSTERERS 135 



but with all the accuracy with which Leonardo da 

 Vinci struck a circle with his pencil, to testify his 

 mastery, cuts the leaf again in that form, and as 

 surely : and three or four, or five or six times, 

 repeats this operation, returning each time with 

 each piece, so many having been variously observed. 

 The separation between the cells being thus con- 

 solidated, it is further thickened by the lateral, 

 spare, protruding edge of the leaf first introduced 

 lapping over it." 



In the same manner other cells, to the number 

 of four or five, are formed above the first, and 

 any space remaining in the tube is filled up with 

 earth. The bee then bores another tube, and 

 repeats the process until her eggs are exhausted. 

 When the larva has consumed its food-store it 

 spins a lustrous silken cocoon attached to the 

 hangings of its cells, and undergoes the changes 

 into chrysalis and perfect bee. 



Our other native species proceed in a similar 

 manner, though some of them work in different 

 materials. Thus M. circumcincta makes her ex- 

 cavations in the ground of banks, but lines them 

 with rose-leaves ; M. argentata mines in sand, and 

 sometimes uses the leaves of the bird's-foot trefoil 

 {Lotus corniculatus) for her cells ; M. ligneseca, like 

 M. willughbiella and M. centuncularis, make theirs 

 usually in wood, and M. versicolor has been found 

 nesting in the stumps of broom (Sarotbamnus 

 scoparius). M. centuncularis again has sometimes 

 been found to use the petals of the garden geranium 



