MASON- ANTS. • 227 



find the apartments, as well as the large open spaces, 

 filled with adult ants ; and always observed their pupae 

 collected in the apartments more or less near the surface. 

 This, however, seems regulated b}^ the hour of the day, 

 and the temperature : for in this respect these ants are 

 endowed with great sensibility, and know the degree of 

 heat best adapted for their young. The ant-hill contains, 

 sometimes, more than twenty stories in its upper portion, 

 and at least as many under the surface of the ground. By 

 this arrangement the ants are enabled, with the greatest 

 facility, to regulate the heat. When a too burning sun 

 over-heats their upper apartments, ihey withdraw their 

 little ones to the bottom of the ant-hill. The ground-floor 

 becoming, in its turn, uninhabitable during the rain}^ 

 season, the ants of this species transport what most interests 

 them to the higher stories ; and it is there we find them 

 more usually assembled, with their eggs and pupae, when 

 the subterranean apartments are submerged." * 



Ants have a great dislike to water, when it exceeds that 

 of a light shower to moisten their building materials. 

 One species, mentioned by Azara as indigenous to South 

 America, instinctively builds a nest from three to six 

 feet high,t to provide against the inundations during the 

 rainy season. Even this, however, does not always save 

 them from submersion ; and, when that occurs, they are 

 compelled, in order to prevent themselves from being 

 swept away, to form a group somewhat similar to the 

 curtain of the wax-workers of hive-bees (see p. 99). The 

 ants constituting the basis of this group, lay hold of some 

 shrub for security, while their companions hold on by 

 them ; and thus the whole colony, forming an animated raft, 

 floats on the surface of the water till the inundation (which 

 seldom continues longer than a day or two) subsides. V\e 

 confess, however, that we are somewhat sceptical respecting 

 this story, notwithstanding the very high character of the 

 Spanish naturalist. 



* M. P. Huber on Ants, p. 20. 



t Stedman's Simnam, vol. i., p. IGO. 



