THE EUMENES 211 



When she comes across a Httle white shell, she hastens 

 to beautify her dome with it; should fortune smile 

 and empty snail-shells abound, she encrusts the whole 

 fabric with them, until it becomes the supreme expres- 

 sion of her artistic taste. Is this so? Or is it not so? 

 Who shall decide ? 



The nest of Eiimenes pomiformis is the size of an 

 average cherry and constructed of pure mortar, without 

 the least outward pebblework. Its shape is exactly 

 similar to that which we have just described. When 

 built upon a horizontal base of sufficient extent, it is 

 a dome with a central neck, funneled like the mouth 

 of an urn. But when the foundation is reduced to a 

 mere point, as on the twig of a shrub, the nest becomes 

 a spherical capsule, always, of course, surmounted by 

 a neck. It is then a miniature specimen of exotic 

 pottery, a paunchy alcarraza. Its thickness is very 

 slight, less than that of a sheet of paper; it crushes 

 under the least effort of the fingers. The outside is 

 not quite even. It displays wrinkles and seams, due 

 to the different courses of mortar, or else knotty pro- 

 tuberances distributed almost concentrically. 



Both Hymenoptera accumulate caterpillars in their 

 coffers, whether domes or jars. Let us give an abstract 

 of the bill of fare. These documents, for all their dry- 

 ness, possess a value; they will enable whoso cares 

 to interest himself in the Eumenes to perceive to what 

 extent instinct varies the diet, according to the place 

 and season. The food is plentiful, but lacks variety. 

 It consists of tiny caterpillars, by which I mean the 



