134 A NATURALIST IN HIMALAYA 



its leg through the air seeking for the lost radii. 

 Nevertheless, it still circled on. A seventh radius was 

 divided, so that now almost half the radii in the snare 

 had been severed, and all were adjoining radii. The 

 bridge was now eight times the normal length, and 

 the space across which the viscid thread had to be 

 drawn was eight times the normal width. Neverthe- 

 less, the spider struggled on in the same mechanical 

 routine until the division of the seventh radius made 

 its difficulties acute. The bridge was now so slack 

 that the spider could scarcely cross it, and I could 

 almost have put my fist into the vacant space in the 

 snare. The bridge was almost impassable, yet the 

 spider persisted in its blind circuit, adhering rigidly to 

 its routine. 



Instinct is the guiding factor of a spider's life ; it is 

 instinct that compels it in the same undeviating course. 

 Introduce difficulties in its circuit, raise increasing 

 barriers to oppose the instinctive progress, build up 

 obstructions to impede the blind routine, and the spider 

 can do nothing to overcome them ; it can only struggle 

 in its course. It can appreciate none of these difficul- 

 ties ; it can understand none of these obstacles ; all it 

 can do is but circle on. 



Another experiment leads us to a similar result, 

 that the spider knows nothing of its work. A snare 

 of the Araneus was under construction. Four turns 

 of the viscid spiral were complete. In one segment 

 between two radii I divided the spiral as fast as it was 

 laid down. Thus, with the exception of the four turns 

 that existed before I commenced the experiment, no 

 other filaments were allowed to remain in that segment. 

 The spider circled round and round weaving with 



