The Dung-Beetles of the Pampas 



hatching-chamber; outside, at the tip of the 

 nipple, it spreads into a wide mouth. This 

 is the ventilating-shaft, protected against in- 

 truders by its extreme narrowness and by 

 grains of dust which obstruct it a Httle with- 

 out stopping it up. I said it was simply 

 marvellous. Was I wrong? If a construct- 

 ion of this sort is a fortuitous result, we must 

 admit that blind chance is gifted with ex- 

 traordinary powers of foresight. 



How does the clumsy insect manage to 

 accomplish so delicate and complex a piece 

 of building? Exploring the pampas as I 

 do through the eyes of an intermediary, my 

 only guide in this question is the structure 

 of the work, a structure whence we can de- 

 duct the workman's method without going 

 far astray. I therefore imagine the build- 

 ing to proceed in this manner : a small car- 

 case is found, the oozing of which has soft- 

 ened the underlying loam. The insect col- 

 lects more or less of this loam, according to 

 the richness of the vein. There are no pre- 

 cise limits here. If the plastic material be 

 plentiful, the collector is lavish with it and 

 the provision-box becomes all the more solid. 

 Then enormous calabashes are obtained, ex- 

 ceeding a Hen's egg in volume and formed of 

 an outer wall three-quarters of an inch thick. 

 257 



