54 THE WONDERS OF INSTINCT 



dened with his extravagant head-dress, will emerge from 

 the darkness through this opening when the summer 

 heats arrive. 



After the cares of the future come the cares of the 

 present. The larva, which has just opened the aperture 

 of escape, retreats some distance down its gallery and, 

 in the side of the exit-way, digs itself a transformation- 

 chamber more sumptuously furnished and barricaded 

 than any that I have ever seen. It is a roomy niche, 

 shaped like a flattened ellipsoid, the length of which 

 reaches eighty to a hundred millimeters. 1 The two axes 

 of the cross-section vary : the horizontal measures twenty- 

 five to thirty millimeters ; 2 the vertical measures only 

 fifteen. 3 This greater dimension of the cell, where the 

 thickness of the perfect insect is concerned, leaves a cer- 

 tain scope for the action of its legs when the time comes 

 for forcing the barricade, which is more than a close- 

 fitting mummy-case would do. 



The barricade in question, a door which the larva 

 builds to exclude the dangers from without, is two- and 

 even three-fold. Outside, it is a stack of woody refuse, 

 of particles of chopped timber; inside, a mineral hatch, 

 a concave cover, all in one piece, of a chalky white. 

 Pretty often, but not always, there is added to these two 

 layers an inner casing of shavings. Behind this com- 

 pound door, the larva makes its arrangements for the 

 metamorphosis. The sides of the chamber are rasped, 

 thus providing a sort of down formed of raveled woody 



1 3 to 4 inches. — Translator's Note. 

 2 .975 to 1. 17 inch. — Translator's Note. 

 8 .585 inch.— Translator's Note. 



