110 THE VICTORIAN NATURALIST. 



furnished with very sensitive hairs, and serves the purpose of 

 speech as well as touch and taste. It has been thought that 

 they may also possess the sense of smell. I have tried some 

 experiments with M. sanguinea, which do not seem to confirm 

 their appreciation of scent as we understand it. If a very 

 pungent and noxious matter is placed near the antennse they do 

 not hesitate to touch it, although they suffer thereby. They will 

 touch their antennje on wet paint or varnish, so that the sense of 

 smell that would be a warning to us does not seem to be appre- 

 ciated by them. If a drop of their own formic acid is placed 

 near them they will touch it with the antennse, and imme(iiately 

 show signs of distress. If the larva of the cockchafer, which has 

 been impregnated with formic acid by the stings of the ants, is 

 torn open and held towards them, and they touch it with the 

 antennse, they show signs of distress ; the antenna that has 

 touched the affected part will be violently rubbed either on the 

 side of the case or on the ground, the ant walking quickly back- 

 wards. Only the antenna which has touched the objectionable 

 matter will be rubbed, and after a very brief space the ant walks 

 away as if the pain had subsided. When they come into contact 

 with any slimy matter, as, for instance, in grappling with a worm 

 or attacking a slug, both the mandibles and antennae will become 

 coated. They will then seek a soft part of the ground, and rub 

 them in the sand preparatory to cleaning them. This seems to 

 be a very artful operation, for the grains of sand by attraction 

 will, to a certain extent, absorb the matter which they wish to 

 remove, and make it easier for them in the process of cleaning. 



While the foregoing experiments would argue against the sense 

 of smell in the antennse, there are some points in favour of such a 

 faculty. For instance, the power of recognition by touch of the 

 antennse. If two ants from the same nest are separated for a 

 time (I have tested it after a period of months), they recognize 

 each other as friends by a touch of the antennse, but if two ants 

 meet from different nests (even if only a few yards apart) they 

 at once recognize each other as enemies, and a fight ensues. It 

 is not necessary that the antenna of one ant should touch that of 

 the other, for recognition at once takes place if the antenna of 

 one touches any portion of the body of the other. It is difficult 

 to disassociate this process of recognition from the sense of smell, 

 and equally as difficult to see why adjoining nests should differ in 

 that respect. 



In performing their toilet their attitudes are both grotesque 

 and interesting. A favourite position is to turn the abdomen 

 under (like a crayfish), and extend the two hind legs back- 

 wards as props, and then sit straight upright. This relieves 

 the two fore legs, which may be used simultaneously to clean the 

 antennae and mandibles. On the anterior tibia there is an 

 elaborate apparatus, consisting of a brush to clean the antennse 



