ANT COMMUNITIES 



Stealing along their tenuous subways, scarcely larger 

 than a lady's knitting-needle, they enter a Formica 

 nursery, where a bunch of cocoons has been stored in 

 fancied security. These they mount, perforate, cut the 

 included pupa? to pieces, and bear the parts away in 

 their mandibles or absorbed within their crops. 



Janet observed their method in an artificial nest of 

 Solenopsis fugax and Formica rufibarbis. He fed the 

 former daily about ten cocoons of Lasius queens, placing 

 them near the formicary gate. Soon the little thief- 

 ants appeared. From ten to thirty so small they are 

 would climb upon a single cocoon, which ere long was 

 dotted with minute perforations that at last united in a 

 rift that exposed the contents. Then the fierce lilliputians 

 fell upon their victim, cut into it, sucked its vital juices, 

 and tore it into minute piecelets, which they bore into 

 the nest interior. 



One wonders how all this thieving and killing can go 

 on unnoticed and unavenged by the Formicas ? A glance 

 at the diagram will show that the diminutive avenues 

 of the aggressors are a secure refuge for them, into which 

 the Formicas could not follow, even if they were detect- 

 ed. Moreover, such an experienced naturalist as Doctor 

 Forel is inclined to believe that, when the two species 

 chance to meet, the minute size of the thief-ants makes 

 them invisible to their hosts, so that the burglarizing 

 and murdering may go on unnoticed. How that could 

 seriously affect the situation, in view of the antennal 

 sensitiveness to other distinctions, does not clearly ap- 

 pear. Besides, small as they are, the thieves are armed 

 with formidable stings, and are so numerous that they 

 are antagonists not to be despised. 



It must also be remembered that the secret and 



256 



