ANTS SPECIAL SENSES. 33 



the glass sides of their artificial nests to enjoy the light of 

 a lamp. Possibly, therefore, the scale of preference to 

 lights of different colours would be found in this genus to 

 be the reverse of that which Sir John Lubbock has found 

 in the case of the British species. 



As regards hearing, Sir John Lubbock found that 

 sounds of various kinds do not produce any effect upon 

 the insects. Tuning-forks and violin notes, shouting, 

 whistling, &c., were all equally inefficient in producing the 

 slightest influence upon the animals ; and experiments 

 with sensitive flames, microphone, telephone, &c., failed to 

 yield any evidence of ants emitting sounds inaudible to 

 human ears. 



Lastly, as regards the sense of smell, Sir John Lubbock 

 found that on bringing a camel's-hair brush steeped in 

 various strong scents near where ants were passing, ' some 

 went on without taking any notice, but others stopped, 

 and evidently perceiving the smell, turned back. Soon, 

 however, they returned, and passed the scented pencil. 

 After doing this two or three times, they generally took 

 no further notice of the scent. This experiment left no 

 doubt on my mind." In other cases the ants were observed 

 to wave about and throw back their antenna? when the 

 scented pencil was brought near. 



That ants track one another by scent was long ago 

 mentioned by Huber, and also that they depend on this 

 sense for their power of finding supplies which have been 

 previously found by other ants. Huber proved their 

 power of tracking a path previously pursued by their 

 friends, by drawing his finger across the trail, so oblite- 

 rating the scent at that point, and observing that when the 

 ants arrived at that point they became confused and ran 

 about in various directions till they again came upon the 

 trail on the other side of the interrupted space, when they 

 proceeded on their way as before. The more numerous 

 and systematic experiments of Sir John Lubbock have 

 fully corroborated Huber's observations, so far as these 

 points are concerned. Thus, to give only one or two of 

 these experiments ; in the accompanying woodcut (Fig. 1 ) 

 A is the nest, B a board, n f g slips of paper, h and m 



