264 WASP STUDIES AFIELD 



Experiment Xb 



The wasps from nests 24 and 25 for Experiment IX had 

 been removed on the preceding day ; they were all still absent 

 from the nest at 7 o'clock on the morning of July 18. But 

 those which had escaped the first collection had by this time 

 returned, and four of these were taken. The very fact that 

 these escaped from the nest on the previous day when the 

 catch was made indicates that they were the older and wiser 

 heads, and the results should be regarded in this light. One 

 was taken from nest 24 and three from nest 25. These 

 were released on the hill-top at 8 o'clock, and when we ar- 

 rived at the shed below at 8 150, they had all returned more 

 speedily than we. 



It is too great a deduction .from limited data to say that 

 it is easier for the wasps whose home is in the valley to 

 reach it from a hill-top than vice versa, but the experiment 

 does show that it is possible for wasps to find their way 

 home from hill-tops if they are taken from their homes 

 below, regardless of what bees do. 5 In Experiment IX, where 

 they returned from a lower plane to the same hill-top, the 

 route was by a two-mile flight and the ascent was a grad- 

 ual one up the gently-sloping side of the hill, whereas in 

 this experiment the ascent would have been up the steepest 

 side of the hill. 



Experiment XI 



While we were eager to make some experiments on the 

 homing flight of these wasps from greater distances, these 

 had to be postponed as the material available at this time 

 was unsuitable. 



It seemed fitting, therefore, to devote the available material 

 to experiments attempting to ascertain by what sense they 



5 Experiment XIII shows that antennaeless wasps are capable of 

 making the downward flight successfully. 



