140 NATURAL HISTORY. [CH. VII. 



view of hastening this event, they deposite them in 

 the warmest part of their dwelling. 



The mode in which the habitations of the ants are 

 constructed varies according to the species of this 

 insect. Some excavate their dwellings, and are 

 hence denominated mining' ants; others build them 

 on the surface of the ground, and are, in consequence, 

 termed mason ants ; and a third species take up their 

 residence in liollow trees. But whatever may be 

 the mode in which they form their habitations, they 

 always contrive to shelter themselves completely 

 from the rain. The longest and loftiest chamber is 

 placed near the centre of the nest, and here all the 

 galleries terminate ; the subterranean chambers are 

 horizontal. In the evening, the aperture of the 

 nests of some ants is always closed, and in the 

 morning reopened; but according to Huber, the 

 brown ant has been seen to work during a moon- 

 light night. 



Having in the daytime noticed some aphides upon 

 a thistle, he examined it again in the n'ght about 

 eleven o'clock, and found his ants busj' milking 

 their cows. At the same hour, another night, he 

 observed, on an elder-tree, the little negro-ant en- 

 gaged in the same employment. 



From the result of their labours, it might be in- 

 ferred that they were actuated by a common me- 

 chanical instinct, yet this is by no means the case : 

 no two apartments are alike in the same nest ; and 

 no two nests have exactly the same arrangements. 

 Each ant seems capable of conceiving a particular 

 plan, which is in some manner made intelligible to 

 the rest, and practically executed. If pieces of 

 straw be placed conveniently for its purpose, an ant, 

 after careful examination, proceeds to make use of 

 this appropriate supply of materials. In another 

 case it would have to drag bits of stubble, then 

 arrange them, and then build. The operations of 

 these insects vary vei-y much from the beautiful and 



