Chap. II. THEIR INTELLIGENCE. 79 



leaves had been left out during several nights, 

 the tips of the needles of many leaves were 

 tied together with fine thread. Of leaves 

 thus treated 150 were drawn into burrows — 

 123 by the base and 27 by the tied tips ; so 

 that between four and five times as many were 

 drawn in by the base as by the tip. It is 

 possible that the short cut-off ends of the 

 thread with which they were tied, may have 

 tempted the worms to drag in a larger propor- 

 tional number by the tips than when cement 

 was used. Of the leaves with tied and 

 cemented tips taken together (271 in number) 

 85 per cent, were drawn in by the base and 

 15 per cent, by the tips. We may therefore 

 infer that it is not the divergence of the two 

 needles which leads worms in a state of nature 

 almost invariably to drag pine-leaves into 

 their burrows by the base. Nor can it be the 

 sharpness of the points of the needles which 

 determines them ; for, as we have seen, many 

 leaves with the points cut off were drawn in 

 by their bases. We are thus led to conclude, 

 that with pine-leaves there must be something 

 attractive to worms in the base, notwithstand- 

 ing that few ordinary leaves are drawn in by 

 the base or foot-stalk. 



