Manchester Memoirs, Vol. liii. (1909), No. /80. 5 



they might be termed, the aphides are able to continue 

 sucking the juices of the plant and at the same time they 

 are not only protected from their enemies but also from 

 alien ants. The protection from cold is also important, 

 as Brandes (1894) has found that aphides are most active 

 during the warmer part of the day, so that in keeping 

 them warm the ants would also be obtaining a larger 

 supply of the secretion from them. In addition to these 

 explanations of the tent-building habits of ants, Wheeler 

 (/.r.) also suggests that the tents may be to prevent the 

 escape of the aphides to other plants or other parts of the 

 same plant. 



The evolution of the forms of the tents which are 

 found iii the different genera of tent-building ants may 

 have started with the small earthen cell covering a few 

 aphides : this may have been constructed either on the 

 stem or by filling the space formed by the inrolling of 

 certain of the leaves. Further enlargement and elabora- 

 tion would lead to the formation of a spherical or 

 cylindrical tent having the stem as axis, and finally, to 

 secure for themselves the greatest comfort and conveni- 

 ence, the ants would connect these tents either with the 

 earth or with their subterranean nests by means of covered 

 passages. 



The phenomenon does not appear to be common in 

 Japan, for though travelling widely over the country, the 

 observer noted these galleries and tents only in one 

 district. Simple nest building ants inhabiting trees were 

 reported as being widely distributed, but the type of 

 structure here described does not seem to have been 

 noted hitherto, and may possibly be a local peculiarity of 

 the ants. 



