HARVESTING ANTS. 3& 



able to secure better specimens of the tunnels for draw- 

 ing (Figs. B, B 1, Plate V.,p. 33). These drawings may 

 be taken as representing also the size and shape of 

 the tunnels in the former nest, which were for the 

 most part like these, beautifully cylindrical, as is shown 

 in the front view of the tunnel at B 1. In one nest 

 of harhara I found a curious hollow spherical dome, 

 about an inch in diameter, the walls of which were 

 constructed of hardened earth about two lines thick, 

 and having a hirge circular aperture at the top and a 

 very small one below (Figs. D and D 1, Plate VI.). This 

 dome was imbedded below in earth which adhered 

 to it, but it was otherwise easily separable from the 

 soil ; its inner walls were smoothed with great nicety. 

 It has been suggested to me that this spherical 

 chamber was originally the work of a scarabseus, which 

 had chanced to bury the ball containing its eggs close 

 to the nest of the ants, and that the latter had appro- 

 priated it after the departure of the beetle grubs. 

 This may perhaps have been the case, but the dome 

 was rather larger than the ball usually formed by 

 the scarab beetle, and I have never seen one of 

 these balls surrounded by a hardened case. The 

 chamber thus constructed was employed as a granary, 

 and filled, as well as the adjacent passages, with the 

 grain of a grass {Tragus racemosus), still enclosed in the 

 husks, among which I detected several ants at work, 

 and also some minute white semi-transparent creatures, 

 like spring-tails [Podunis], which abound in these ants' 

 nests. Besides this spring-tail it is common to find in 

 the galleries and granaries of Atta structor and A. har- 

 hara, certain silky j^ellowish-white " silver fish" {Le- 

 jpisma), a small white woodlouse which does not 



D 2 



