218 



THE SOLITARY WASPS. 



on one side of the nest. (PL IX., fig. 1.) C. nigrescens, too, be- 

 gan with semi-circles, while C. clypeata flew entirely around 

 and around the opening. The contrast between the deliberate 

 movements of Astata and the rapid flight of Cerceris is quite 

 remarkable. 



The last wasp that we studied in the summer of 1897 was 

 Tachytes sp.1 This species stores her nest with young grass- 

 hoppers and after catching them she usually has the greatest 

 difficulty in getting back to her nest. The above diagrams show 

 just the number of turns made by one individual in bringing 

 home her two grasshoppers. 



We have now given a sufficient number of instances, from 

 widely separated genera, to show the care that is taken by wasps 

 to acquaint themselves with the surroundings of their nests. It 



