﻿•S6 Journal New York Ent. Soc. [Vol. hi. 



less level, are, naturally, less covered than elsewhere. It was in such 

 places that the domes abounded ; those found over quarries and 

 elsewhere, previously alluded to, were, like those in higher areas, 

 personally examined by me, and all were found to be in shallow 

 earth. This feature furnishes the second condition of the theory ; 

 the first is a matter of indisputable record. 



Among the places where domed burrows were found in thin 

 soil were Nyack ; Upper Nyack ; South Nyack ; Grandview and 

 Piermont ; and on top of the Palisades near Alpine; Closter; 

 Demarest ; Cresskill ; Englewood ; New Durham and Fort Lee. 

 Several of these areas had been burnt over. 



A correspondent writes me that in a dome area observed by 

 him the structures were built after a fire, as shown by their con- 

 taining burnt twigs. But this is just what would occur after a 

 fire : The builders would come in contact with them in their work 

 and they would be incorporated. I have many such specimens, 

 A professional entomologist who visited the same spot writes that 

 the case I reported from Nyack to the New York Times (wherein 

 it was stated that the ground had been burnt over before the 

 domes were built,) so fitted to the one observed by him that he 

 was inclined to think it was an account of the one he had seen, and 

 that the name of the locality had in some way been changed. It 

 is not claimed that fire is necessary to revive the pupre ; but it is 

 evident that in some cases it has been effectual ; in others the ab- 

 normal heat of the sun was sufficient. 



Professor John B. Smith reports that the structures were 

 found near a quarry at Newark, N. J., and at Port Jefferson, in 

 the same state. In the latter case vast numbers were observed by 

 Dr. J. Howard Willets who possesses substantial proof that they 

 were built five or six day after a forest fire; the domes close to- 

 gether, and ending abruptly at the edge of the burnt area. 



It is not claimed that all the dome aggregations were in soil 

 over rocks. The burrows might have been shallow from a variety 

 of causes. In one case reported there was a sub-stratum of coarse 

 sand, too incoherant for burrowing. In other places the sub-soil 

 might have been wet, peaty, or gravelly. Even in deep soil some 

 pupae would be nearer the surface than others, and if near enough 

 to be prematurely revived by the heat would erect their protective 

 domes ; among which the open burrows of the deeper pupae would 



