xxiv The Life of the Spider 



shell. In those conditions, it is a dainty cup, 

 half spherical, with torn edges, lengthened out 

 below into a delicate, winding stalk.' 



Now, how is this miraculous explosion pro- 

 duced ? J. H. Fabre assumes that : 



* Very slowly, as the little animal takes shape 

 and grows, this bladder-shaped reservoir receives 

 the products of the work of respiration per- 

 formed under the cover of the outer membrane. 

 Instead of being expelled through the egg-shell, 

 the carbonic acid, the incessant result of the 

 vital oxidization, is accumulated in this sort 

 of gasometer, inflates and distends it and 

 presses upon the lid. When the insect is ripe 

 for hatching, a superadded activity in the 

 respiration completes the inflation, which per- 

 haps has been preparing since the first evolu- 

 tion of the germ. At last, yielding to the 

 increasing pressure of the gaseous bladder, the 

 lid becomes unsealed. The Chick in its shell 

 has its air-chamber ; the young Reduvius has 

 its bomb of carbonic acid : it frees itself in the 

 act of breathing.' 



