The Sacred Beetle and Others 



proved, in a more definite fashion, by the 

 following experiment. In July, the period 

 of active nidification, I place in wooden or 

 cardboard boxes a dozen pears unearthed 

 that morning from their native burrows. 

 These boxes, carefully closed, are put away 

 In the dark, in my study, where the same 

 temperature prevails as outside. Well, in 

 none of them is the infant reared: sometimes 

 the egg shrivels; sometimes the worm is 

 hatched, but very soon dies. On the other 

 hand, in tin boxes or glass receptacles, every- 

 thing goes well: not one attempt at rearing 

 fails. 



Whence do these differences arise? 

 Simply from this : in the high temperature 

 of July, evaporation proceeds apace under 

 the permeable wooden or cardboard screen; 

 the food-pear dries up; and the unfortunate 

 worm dies of hunger. In the impermeable 

 tin boxes, in the carefully-sealed glass 

 receptacles, evaporation does not take place; 

 the provisions retain their softness; and the 

 grubs thrive as well as In their native 

 burrow. 



The insect employs two methods to ward 



off the danger of desiccation. In the first 



place, it compresses the outer layer with all 



the strength of Its stout, flat fore-arms, 



94 



