206 ANTS. 



edges of the stones \vith earth or plant detritus into which they often 

 extend their galleries and chambers for the aeration and incubation of 

 the brood. Rven the mound-building forms frequently start their 

 nests in this way and gradually heap the detritus up over the stones till 

 they are concealed under typical domes and the original lapidicolous 

 habit of the colony is no longer recognizable. In the North American 

 forests the logs and branches strewn about on the ground afford a sub- 

 stitute for stones and cover the nests of many glade ants, such as F. 

 rnbicunda, intctjra, lucinorrhoidalis. Apheenogaster fulva, etc., F. intctjra 

 (Fig. 112) in the Eastern and hcemorrhoidalis in the Western States fill 

 out the spaces in and under logs with vegetable detritus. Ants are not 

 fond of nesting under cow dung, but in Texas I have found Solenopsis 

 i^cininata and Camponotus fumidus resorting to such nesting sites in 

 regions where stones were scarce and moisture and protection from the 

 intense heat of the sun nowhere else to be found. Forel has made simi- 

 lar observations in the high mountain pastures of Switzerland (1874). 



