WASPS, SOCIAL AND SOLITARY 



signs of life at the end of two weeks. Urnaria stores 

 two caterpillars, and in more than one instance the 

 second one died and became discolored before the first 

 one was entirely eaten. The wasp larva did not, as 

 might have been expected, find fault with this arrange- 

 ment, but proceeded to attack number two with good 

 appetite, ate it all up, and then spun its cocoon as 

 though nothing unpleasant had occurred. 



The second condition was also violated. In one case 

 the bite of the newly hatched larva caused the caterpillar 

 to rear upon end in so violent a manner that it looked as 

 though the little creature would surely be dislodged. 

 Another caterpillar kept up a continuous wriggling with- 

 out any external stimulation, and when it was touched it 

 rolled about almost as these larvae do in a healthy state, 

 and yet the egg was not shaken off. The caterpillar 

 which received but a single sting, although not motion- 

 less, would have been a safer repository for the egg than 

 either of these. Others fulfilled Fabre's condition per- 

 fectly, lying immovable except when stimulated, and then 

 responding only by a slight quivering of the legs or skin. 



Among the fifteen caterpillars that we have taken 

 from the nests of urnaria three kinds are represented, 

 twelve of them belonging to one species, two to the sec- 

 ond, and one to the third. 



