496 THE POPULAR SCIENCE MONTHLY, 



described other species of ants (genus Atta) as fond of light. It would 

 be interesting for any one who has an opportunity to try whether ants 

 of this genus do not show toward the rays of the spectrum a scale of 

 preference the reverse of that which Sir John Lubbock described. 



As regards hearing, Sir John found that sounds of various kinds do 

 not produce any effect upon the insects, nor could he obtain any evi- 

 dence of their emitting sounds, either audible or inaudible to human 

 ears. 



It has long been known that the sense of smell in ants is highly 

 developed, and it appears to be the sense on which, like dogs, they 

 mainly rely. Huber proved that they track one another's footsteps 

 in finding their way to food, etc.; for he observed, on drawing his 

 finger across the trail so as to obliterate the scent, that the ants be- 

 came confused and ran about in various directions, till they again came 

 upon the trail on the other side of the interrupted space. By many 

 ingeniously devised experiments Lubbock has amply confirmed Huber's 

 statements, and concludes that in finding treasure "they are guided in 

 some cases by sight, while in others they track one another by scent " 

 depending, however, more upon scent than upon sight. 



There can be little doubt that ants have a sense of taste, as they 

 are so well able to distinguish sugary substances ; and it is unquestion- 

 able that in their antenna they possess highly elaborated organs of 

 touch. 



Sexse of DiRECTiois". It is certain that ants, in common with many 

 other animals, possess some unaccountable sense of direction, whereby 

 they are able to find their way independently of landmarks, etc. Sir 

 John Lubbock tried a number of experiments in this connection, of 

 which the following is perhaps the most conclusive : Between the nest 

 and the food he placed a hat -box, in each of two opposite sides of 

 which he bored a small hole, so that the ants, in passing from the nest 

 to the food and back again, had to go in at one hole and out at the 

 other. The box was fixed upon a pivot, where it could be easily 

 rotated, and, when the ants had well learned their way to the food 

 through the box, the latter was turned half round as soon as an ant 

 had entered it ; " but in every case the ant turned too, thus retaining 

 her direction." 



Sir John then placed in the stead of a hat-box a disk of white paper. 

 When an ant was on the disk making toward the food, he gently drew 

 the paper to the other side of the food, so that the ant was conveyed 

 by the moving surface in the same direction as that in which she was 

 going, but beyond the point to which she intended to go. Under these 

 circumstances the ant did not turn round, but went on to the farther 

 edge of the disk, " when she seemed a good deal surprised at finding 

 where she was." 



These results seem to indicate that the sense of direction is due 

 to a process of registering all the changes of direction which may be 



