220 ANIMAL INTELLIGENCE. 



between themselves and the foe. I once saw one of the false 

 spiders, or harvest-men (Phalangidce), standing in the midst of an 

 army of ants, and with the greatest circumspection and cool- 

 ness lifting, one after the other, its long legs, which supported 

 its body above their reach. Sometimes as many as five out of 

 its eight legs would be lifted at once, and whenever an ant ap- 

 proached one of those on which it stood, there was always a 

 clear space within reach to put down another, so as to be able 

 to hold up the threatened one out of danger. 1 



Mr. L. A. Morgan, writing to Nature ' (Jan. 22, 1 880), 

 gives an account of a spider conveying a large insect from 

 the part of the web where it was caught to the ' larder,' 

 by the following means. The spider first went two or 

 three times backwards and forwards between the head 

 of the insect and the main strand of the web. After 

 this he went about cutting all the threads around the 

 insect till the latter hung by the head strands alone. 

 The spider then fixed a thread to the tail end, and by 

 this dragged the carcass as far on its way to the larder 

 as the head strands would permit. As soon as these were 

 taut, he made the tail rope fast, went back to the head 

 rope and cut it ; then he attached himself to the head 

 and pulled the body towards the larder, until the tail rope 

 was taut. In this way, by alternately cutting the head 

 and tail ropes and dragging the insect bit by bit, he con- 

 veyed it safely to the larder. 



But the practical acquaintance with mechanical prin- 

 ciples which this observation displays is perhaps not so 

 remarkable as that which is sometimes shown by spiders 

 when they find that a widely spread web is not tightly 

 enough stretched, and as a consequence is to an incon- 

 venient extent swayed about by the wind. Under such 

 circumstances these animals have been observed to sus- 

 pend to their webs small stones or other heavy objects, 

 the weight of which serves to steady the whole system. 

 Grleditsch saw a spider so circumstanced let itself down to 

 the ground by means of a thread, seize a small stone, re- 

 mount, and fasten the stone to the lower part of its web, 

 at a height sufficient to enable animals and men to walk 



1 Naturalist in Nicaragua, p. 19. 



