40 A NATURALIST IN HIMALAYA 



slcib of slate lying at an angle of about forty-five 

 degrees. The ants, in order to pass from the ant- 

 ficld to the nest, had to climb up this slippery slate. 

 The journey was a very difficult one, and an ant 

 scarcely ever succeeded in climbing up the slate 

 without falling down many times and having to 

 recommence the journey again and again. Numbers 

 of ants in this way got lost ; many others were unable 

 to reach the nest by nightfall, and probably hid them- 

 selves away beneath the stones. The nest rapidly 

 dwindled as it lost its workers, but the remaining ants 

 still persisted in their struggle up the slippery slate. 

 By travelling round the edge of the slate, a not very 

 much longer journey, the ants could have gathered 

 their harvest in safety, or they might have migrated 

 to a more suitable nest. But these expedients never 

 seemed to strike the ants ; they persevered in their 

 impossible task until all were destroyed. 



On another evening, while exploring a little ravine, 

 I observed a more obvious instance of their lack of 

 intelligence. Harvesters, I have already mentioned, 

 carry the chaff and husks of their seeds out of the nest, 

 and these they carefully pile up into a little refuse heap 

 some eight or ten inches clear of the nest. Now I 

 found a nest-opening on the face of a vertical wall of 

 clay bordering the side of the ravine. The ants were 

 carrying their loads up the perpendicular wall. The 

 nest interested me and I stayed to watch the work, as 

 it was evident that to transport the seeds up to a nest 

 in such a position must entail much more labour than 

 if the nest was situated on the level around. How- 

 ever, when I noticed the pile of chaff and husks lying 

 on the floor of the ravine below the mouth of the 



