THE EUMENIDAE 337 



generation they remain persistently in the place where they 

 were born, and frequently an entire population in a locality 

 is exterminated just because of their inability or unwilling- 

 ness to move from a chosen spot, even when it appears 

 to us that migration would be very easy. And so it was 

 with this particular group of O. foraminatus. It seems 

 they were introduced into this locality about eight years 

 ago, at a time when the brick manufacturing company piled 

 several carloads of logs in the field. These logs have been 

 hauled away, from time to time, by cartloads and used for 

 starting the kiln fires. It is possible that they were intro- 

 duced in some stage of their development with the logs, 

 and, finding everything to their liking, have occupied the 

 site generation after generation, never going even to the 

 fence-posts or other wooden structures near by. As a result 

 of this inability to go even a little way from the place of 

 their birth, their numbers have grown less and less, as the 

 logs have been used ; and now, when the last load will have 

 gone to feed the flames, there seems no hope of anything 

 but extermination for this lot. We have made diligent 

 search about the region to find even a few of them taking 

 up their abode in some more permanent structure, but with- 

 out success. If, like our Bembi.v nubilipennis and Scolia 

 dubia, they cannot disseminate over different parts of a 

 restricted area, how is it possible for them to cover distinct 

 or remote areas? 



Hungerford and Williams dug them out of a stump in 

 Decatur County, Kansas, and found the cells separated by 

 partitions of mud. 



After so recently deploring the probable extermination 

 of many of these wasps on account of their lack of adapta- 

 tion to other places of abode than the logs, we were grati- 

 fied to have discovered in another area at least one case in 

 which this insect had used a hollow twig. This elderberry 



