AMMOPHILA AND HER CATERPILLARS 



mother continually passes in and out, as in Bembex 

 and Oxybelus. 



Fabre thinks that hirsuta has the habit, unusual for 

 Ammophila, of catching her prey first and then digging 

 the hole in which she bestows it. As she takes only one 

 large caterpillar she is thus relieved of the necessity of 

 closing the nest more than once. 



As has been said, urnaria usually hunts a long time 

 before she finds her caterpillar, and one or two days 

 may pass before anything is put into the nest. During 

 this prolonged search she often revisits the spot, and 

 thus keeps fresh the memory of its locality. As soon as 

 the first caterpillar is stored she lays an egg on it, and 

 then closes the nest as before. The second one may be 

 brought in within a few hours ; but in one instance that 

 came under our notice we feel sure that the interval 

 was as much as three days. We saw the interment of the 

 second caterpillar, and upon excavating, found on the 

 first one a larva at least a day old; we suppose that at 

 least two days had elapsed between the laying and the 

 hatching of the egg. 



When the provisioning is completed the time arrives 

 for the final closing of the nest ; and in this, as in all the 

 processes of Ammophila, the character of the work dif- 

 fers with the individual. For example, of two wasps that 



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