The Life of the Caterpillar 



has caught from beneath and meet to form a 

 transversal crest, perpendicular to the crea- 

 ture's back. 



This hairy erection produces a sudden 

 modification in the caterpillar's aspect. The 

 red shiny bristles have disappeared, buried 

 under the dark skin; the white hairs, now 

 standing on end, form a hirsute mane; an 

 ashy tinge has crept into the general colour 

 of the costume. 



When calm is restored, as soon happens, 

 the slits open and yawn afresh; the sensitive 

 protuberances emerge, quick to disappear 

 once more should any cause for alarm occur. 

 These alternate expansions and contractions 

 are rapidly repeated. I provoke them at will 

 in various ways. A slight puff of tobacco- 

 smoke immediately causes the stomata to 

 yawn and the protuberances to emerge. One 

 would think that the insect was putting itself 

 on its guard and displaying some special ap- 

 paratus of information. Before long the pro- 

 tuberances go in again. A second puff of 

 smoke brings them out once more. But, if 

 the smoke is too abundant, too acrid, the 

 caterpillar wriggles and writhes without open- 

 ing his apparatus. 



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