i6o INSECT LIFE 



XI 



Whether in its natural position or on its back or 

 side, the creature retains whichever is given it. Con- 

 stant oscillations of the antennae, and, at intervals, 

 some pulsations of the stomach and movements of 

 the mouthpieces, are the only sign of life. Motion 

 is destroyed but not feeling, for at the least prick 

 where the skin is thin, the whole body shudders 

 faintly. Perhaps one day physiology will discover 

 in these victims a subject for fine studies on the 

 functions of the nervous system. The Hymen- 

 opteron's sting, incomparably skilful in reaching a 

 given point and inflicting a wound to affect it alone, 

 will replace, with immense advantage, the brutal 

 scalpel of the experimenter, which disembowels 

 where it should lightly touch. Meanwhile, here are 

 the results obtained from the three victims, but from 

 another point of view. 



Only movement of the feet being destroyed, there 

 being no injury save that to the nerve centres, the 

 source of motion, the creature perishes, not from its 

 wound, but from inanition. The experiment was 

 tried thus : 



Two uninjured ephippigers found in the fields 

 were imprisoned without food, one in the dark, the 

 other in the light. In four days the latter died of 

 hunger, in five the former. This difference of a day 

 is easily explained. In the light the creature is 

 more eager to recover liberty, and as every move- 

 ment of the animal machine causes a correspond- 

 ing expenditure of energy, greater activity used 

 up sooner the reserves of the organisation. With 

 light, more agitation and shorter life ; in darkness, 

 less movement and longer life ; both insects fasted 



