262 THE WONDERS OF INSTINCT 



1 8 millimeters ^ in diameter and the largest 24 milli- 

 meters.^ There is room for two cocoons, or three at 

 most, according to their dimensions. 



Now these shells were used by my visitors without 

 any hesitation, perhaps even with more eagerness than 

 the glass tubes, whose slippery sides might easily be a 

 little annoying to the Bee. Some of them were occupied 

 on the first few days of the laying; and the Osmia who 

 had started with a home of this sort would pass next to 

 a second Snail-shell, in the immediate neighborhood of 

 the first, to a third, a fourth and others still, always close 

 together, until her ovaries were emptied. The whole 

 family of one mother w^ould thus be lodged in Snail- 

 shells which were duly marked with the date of the lay- 

 ing and a description of the worker. The faithful ad- 

 herents of the Snail-shell were in the minority. The 

 greater number left the tubes to come to the shells and 

 then went back from the shells to the tubes. All, after 

 filling the spiral staircase with two or three cells, closed 

 the house with a thick earthen stopper on a level with the 

 opening. It was a long and troublesome task, in which 

 the Osmia displayed all her patience as a mother and 

 all her talents as a plasterer. 



When the pupae are sufficiently matured, I proceed to 

 examine these elegant abodes. The contents fill me with 

 joy : they fulfil my anticipations to the letter. The great, 

 the very great majority of the cocoons turn out to be 

 males; here and there, in the bigger cells, a few rare 



1 .7 inch. — Translator's Note. 

 * .936 inch. — Translator's Note. 



