40 DEATH S HEAD SPHINX. 



Then, also, they raise walls, leaving only narrow 

 openings for the passage of a single bee at a time, 

 and which, therefore, can be easily protected. 



" But a period arrives when these galleries are 

 no longer suitable to the bees. At the time that 

 their harvest is abundant, their hive excessively 

 populous, and the formation of new colonies ap- 

 proaches, they demolish the gateways which had 

 been erected in the hour of danger, and which now 

 restrain their impetuosity. Such safeguards have 

 become inconvenient, and they are removed, until 

 new alaiTOS demand tlieir reconstruction. 



" The entrances formed in 1804, were destroyed 

 in spring 180,5. The Sphinx did not appear that 

 year, nor was it seen in the year following ; but it 

 returned in great numbers in autumn 1807. By 

 speedily barricading themselves, the bees prevented 

 tlicir threatened ravages ; but before the departure 

 swarms, in May 1808, they demolished the forti- 

 fications, whose narrow passages prohibited free 

 egress to the multitude. 



" When the entrance to the hive is itself restrict- 

 ed, on care being taken to contract it soon enough 

 to prevent the devastation of their enemies, bees 

 dispense with walling themselves in. We cannot 

 explain their conduct otherwise, than by admitting 

 the evolution of their instinct according as excited 

 by circumstances. 



" But how can the Sphinx alarm colonies so 

 2 



