COLONY FOUNDING OF ACANTHOMYOPS FULIGINOSUS. l8l 



bratns workers were added every day, the niger workers no longer 

 attacking them ; neither did they attack the niger workers, nor the 

 fuliginosus queen. The latter began to swell with eggs again on 

 November 20. On December 31, 1917, there were present 60 

 niger workers and a large number of umbratus workers ; the latter 

 now surrounding the fuliginosus queen. 



Donisthorpe ('19) mentions that in 1918 the umbratus workers 

 in the above-mentioned nest started to kill the niger workers, all 

 having been killed by May 17, 1918, when only one remained, 

 which was killed before the end of the month. The fuliginosus 

 queen gradually got very swollen again, and by May 27 she had 

 laid a small bunch of eggs, which was held up by several umbratus 

 workers. On June 16 two packets of eggs were present, but they 

 were all eventually devoured by the umbratus workers. (The fol- 

 lowing is extracted from my notebook and has not been published 

 before. The virgin female fuliginosus died in May, 1919, having 

 lived in captivity for nearly four years. On April 25, 1919, she 

 was very swollen with eggs, but almost dead, being held up by a 

 number of the umbratus workers ; and on May i she was quite 

 dead, but still carried about by the workers until May 17, when 

 her body was cut up. The umbratus workers then commenced to 

 die off, so they were turned loose in the garden in June.) He 

 further records that on July 17, 1918, he discovered in the New 

 Forest a very interesting mixed colony of A. (D.} fuliginosus and 

 A. (C.) mix t us, which consisted of about two thirds of the former 

 workers to one third of the latter. The two species were walking 

 along together in files on a fence near a railway bridge ; they were 

 quite friendly, tapping antennae and saluting each other when they 

 met on the tracks, as also when placed together in a small tube. 

 The tracks led right down the brickwork of the bridge to the 

 ground beside the line. It was really a beautiful sight, when the 

 sun was shining, to see the jet black fuliginosus and yellow mi.rtus 

 marching in files up and down the wall of the bridge and saluting 

 each other when they met. As mixtus is very subterranean in its 

 habits, it must have learned from the fuliginosus to march in files 

 in the open. The tracks also led to and from a thick bramble 

 grove growing by the side of a fence along the buttress of the 

 bridge, and here the nest was evidently situated. He pointed out 



