ANT COMMUNITIES 



along the branches are vast numbers of aphides, small 

 black insects with brownish thorax and head. Note 

 this one, whose abdomen is raised at an angle of forty- 

 five degrees. Upon the apex is shining a tiny globule of 

 transparent liquid. It is lapped up by the attendant 

 ant, who all the while with alternate strokes of antenna? 

 gently embraces or pats the insect. Again and again in 

 rapid succession the sweet excretion, pumped by the 

 insect from the sap of the tree, and converted by it into 

 the honey-dew of popular speech, gathers in droplets, 

 and is removed by the ants, several of whom have en- 

 joyed the refection in turn. 



At last the aphis, one of mature size, leaves its position 

 and moves along the branch toward the trunk. Its ab- 

 domen is now flattened. Many of its fellows have that 

 organ full and rounded out, and must be uncomfortable. 

 The ants, however, are fast relieving them as the sweet 

 excretion flows, and in the mean time their own abdomens 

 are undergoing a noticeable change. They swell and 

 elongate until the folded membranous bands that unite 

 the segments are pushed out into narrow white ribbons. 

 This is caused by the rapidly expanding crop into which 

 the collected sweets are stored. At last the honey-dew 

 gatherer, whom we may now call a "replete," is satisfied, 

 and turns toward home. It is such as she that compose 

 the descending column of ants upon the tree-trail; and 

 their full, elongated abdomens and white bands form 

 quite a contrast with the round black abdomens of their 

 fellows of the ascending column. 



We are now on the verge of one of the most interest- 

 ing facts in the history of this remarkable community. 

 These repletes belong to a section of the communal 

 foragers, of whom thousands are elsewhere abroad, not 



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