AMMOPHILA AND HER CATERPILLARS. 17 



ing. That on the brown one is crawling- about on the outside. This 

 brown caterpillar is barely alive. 



September 5. The larva in the green caterpillar is eating as before. 

 The brown caterpillar is dead and the parasite has gone inside of its 

 body. 



September 6. The first larva has burrowed into the earth, having 

 eaten all the inside out of its prey. The other one is eating as before. 



September 7. The brown caterpillar's parasite has also burrowed 

 into the ground. 



No. 80. Septenibex 1. Just after noon yesterday we saw an uncom- 

 monlj' large urnaria carry an uncommonly large green caterpillar into 

 her nest. At eleven o'clock this morning we took it out. The egg is 

 on the left side of the seventh segment. 



September 3, 11 A. M. The egg has just hatched. It is nearly three 

 days since it was laid. The weather is cool and it may be for that rea- 

 son that a longer time than usual has elapsed. 



September 4. The larva is growing slowly. 



September 5. The larva grows very slowly. The caterpillar is alive 

 and green. 



September 6. The caterpillar is alive and looks fresh. The larva 

 eats and grows very slowly. 



September 8. The caterpillar is still alive and green. The larva has 

 increased a very little in size. 



Sejitember 10, 5 P. M The larva has grown very fast since yester- 

 day morning. The caterpillar is dead. The last four segments have 

 tiuTied brown, but the rest is of the original green color. 



September 15. The larva is still eating the dark colored remains of 

 the caterpillar. It is now very large and fat and has taken on the 

 green color of the caterpillar which it has devoured. 



September 16. The larva is spinning its cocoon. 



No. 81. August 31. This afternoon we saw an A. gracilis carry a 

 green caterpillar, larger than the one ordinarily taken by urnaria, but 

 not so large as that of No. 80, a long distance (261 ft.) over all sorts of 

 ground. It received very rough usage and when, the wasp having de- 

 serted it, we took it into our possession, it was so contorted that the 

 head and the first four segments were not in a plane with the rest of 

 the body. The third segment, which had been grasped by the mandi- 

 bles of the wasp, was badly bruised and discolored. 



September 1. The caterpillar, as we look at it through the glass 



slide which covers the box in which it lies, continually moves the 



mouth parts and the anterior segments of its body. Now and then it 



slowly lifts the posterior half of its body and then lets it go back. 



2 



