PROVISION FOR REARING THE YOUNG. I3S 



which has been put out of doubt by the illustrious 

 naturalist, is this : the Buprestis are paralysed, not 

 dead ; all the joints of the antennae and legs remain 

 flexible and the intestines in good condition. He 

 was able to dissect some which had been in a state of 

 lethargy for at least a week or a fortnight, although, 

 under normal conditions, these insects in summer 

 decay rapidly, and after forty-eight hours cannot be 

 used for anatomical purposes. Another observer, 

 Paul Marchal, took up this question afresh, and the 

 results which he obtained seemed to indicate an 

 instinct much less firm than earlier studies tended 

 to show.^ 



Genera less skilful in the art of paralysing victims. — 

 These researches show us that in the Cerceris instinct 

 is still subject to defect. In some neighbouring genera 

 we can seize it, as it were, in process of formation. 

 The way in which the Bembex, or Sand Wasp, pro- 

 visions burrows by maternal foresight is much less 

 mechanical than that of the Sphex. It is again Fabre 

 who has described with most care the customs of 

 this hymenopterous insect.^ It hollows out for each 

 egg a chamber communicating with the air by a 

 gallery, and performs this work with little care and 

 very roughly. Less skilful than the others, it does 

 not amass at once all the provisions which its larvae 

 will need during the period of evolution. When the 

 offspring has absorbed the last prey brought, it is 

 necessary to bring a new victim. This insect is 

 scarcely more advanced than birds, who feed their 

 young from day to day. And it is a great labour to 

 re-open every time the gallery which leads to the 



1 Arch, de Zool. exp., 18S7. 



2 Souvenirs eniomologiques, 1879, pp. 225 ei seq. 



