826 THE POPULAR SCIENCE MONTHLY. 



damp earth between the base of the plant and that of the leaf, until the latter 

 was sufficiently bent. After thej had attained their object, they heaped on the 

 buttressing-leaf the materials required for building the arched roof. 



# 



This observation naturally leads to two others by two different ob- 

 servers. Thus, Moggridge says : " I was able to watch the operation 

 of removing roots which had pierced through their galleries, belonging 

 to seedling plants growing on the surface, and which was performed 

 by two ants, one pulling at the free end of the root, and the other 

 gnawing at its fibers where the strain was greatest, until at length it 

 gave way." Again, as previously quoted in another connection, be 

 says that two ants sometimes combine their efforts, one stationing 

 itself near the base of a footstalk and gnawing at the j)oint of greatest 

 tension, while the other hauls upon and twists it. 



The other observer to w^hom I have referred is McCook, who says 

 of the harvesting ants of America that he has seen " the workers, in 

 several cases, leave the point at which they had begun a cutting, 

 ascend the blade, and pass as far toward the point as possible. The 

 blade was thus borne downward, and, as the ant swayed up and down, 

 it really seemed that she was taking advantage of the leverage thus 

 gained, and was bringing the augmented force to bear upon the fract- 

 ure. In two or three cases there appeared to be a division of labor ; 

 that is to say, while the cutter at the roots kept on with his work, 

 another ant climbed the grass-blade and applied the power at the oppo- 

 site end of the lever. This position may have been quite accidental, 

 but it certainly had the appearance of voluntary cooperation." 



These observations serve to render less improbable the following 

 quotation taken from Bingley's account of Captain Cook's expedition 

 in New South Wales, and vouched for by Sir J. Banks. Green ants 

 were seen forming their nests in trees by " bending down several of 

 the leaves, each of which is as broad as a man's hand, and gluing the 

 points of them together so as to form a purse. . . . We saw thousands 

 uniting all their strength to hold them in this position, while other 

 busy multitudes within were employed in applying the gluten that was 

 to prevent their returning back." 



Moggridge says that he has seen the harvesting ants of Europe 

 clustering round the larva of a certain beetle, and directing it toward 

 some small opening in the soil, " which it would quickly enlarge and 

 disappear down " ; and he believes that " these attentions were purely 

 selfish," the ants availing " themselves of the tunnel thus made down 

 into the soil." 



McCook says of the harvesters of America that they dislike shade, 

 so that if a tree grows up in their vicinity and casts a shadow over 

 their nest they forthwith migrate. He gives in this connection a state- 

 ment which I regard as bordering on the incredible, and therefore I 

 desire it to be specially observed that it is not very evident from 



