Chap. II. THEIR INTELLIGENCE. 91 



times through my fingers. Owing to the 

 slime from the worms' bodies, the dirt was 

 not easily washed off. We may therefore 

 conclude that if a triangle, before being 

 dragged in by the apex, had been dragged 

 into a burrow by its base with even a slight 

 degree of force, the basal part would long 

 retain its creases and remain dirty. The con- 

 dition of 89 triangles (65 narrow and 24 

 broad ones), which had been drawn in by the 

 apex, was observed ; and the bases of only 7 

 of them were at all creased, being at the same 

 time generally dirty. Of the 82 uncreased 

 triangles, 14 were dirty at the base; but it 

 does not follow from this fact that these had 

 first been dragged towards the burrows by 

 their bases ; for the worms sometimes covered 

 large portions of the triangles with slime, 

 and these when dragged by the apex over the 

 ground would be dirtied ; and during rainy 

 weather, the triangles were often dirtied over 

 one whole side or over both sides. If the 

 worms had dragged the triangles to the 

 mouths of their burrows by their bases, as often 

 as by their apices, and had then perceived, 

 without actually trying to draw them into the 



