But let us examine the shapeless mass more closely and we shall perceive the number of chambers composing the habitation with the funnelled mouths, each quite distinct and each furnished with its gravel stopper set in the cement.
The Chalicodoma of the Walls employs the same building methods as Eumenes Amedei: in the courses of cement she fixes, on the outside, small stones of minor bulk.

Her work begins by being a turret of rustic art, not without a certain prettiness; then, when the cells are placed side by side, the whole construction degenerates into a lump governed apparently by no architectural rule.

Moreover, the Mason-bee covers her mass of cells with a thick layer of cement, which conceals the original rockwork edifice.

The Eumenes does not resort to this general coating: her building is too strong to need it; she leaves the pebbly facings uncovered, as well as the entrances to the cells.

The two sorts of nests, although constructed of similar materials, are therefore easily distinguished.
The Eumenes' cupola is the work of an artist; and the artist would be sorry to cover his masterpiece with whitewash.