A BARREN PROMISE 93 



enterprise ? A retarding of the progress of the meta- 

 morphosis, but nothing more, apparently. The horn on 

 the corselet would have persisted in its sterility and, 

 sooner or later, would have disappeared. 



I have reasons for my conviction. The abode of the 

 Onthophagus while engaged on his metamorphosis is not 

 deep down ; variations of temperature are easily felt. 

 On the other hand, the seasons are capricious, especially 

 the spring. Under the skies of Provence, the months of 

 May and June, if the mistral lend a hand, have periods 

 when the thermometer drops in such a way as to suggest 

 a return of winter. 



To these vicissitudes let us add the influence of a more 

 northerly climate. The Onthophagi occupy a wide zone 

 of latitude. Those of the north, less favoured by the sun 

 than those of the south, can, if changing circumstances 

 assist at the time of the transformation, undergo long 

 weeks of a decreased temperature which spins out the 

 work of evolution and ought therefore to permit the 

 thoracic armour, at long intervals and casually, to 

 consolidate into a horn. Here and there, then, the con- 

 ditions of a moderate, or even cold temperature, at the 

 time of the nymphosis, are reaHzed without the aid of 

 my artifices. 



Well, what becomes of this surplus time placed at the 

 service of the organic labour ? Does the promised horn 

 ripen ? Not a bit of it : it withers just as it does under 

 the stimulus of a hot sun. The records of entomology 

 have never spoken of an Onthophagus carrjdng a horn 

 upon his corselet. No one would even have suspected the 

 possibility of such an armour, if I had not rumoured the 

 strange appearance of the nymph. The influence of 

 climate, therefore, goes for nothing here. 



