432 TROPICAL WILD LIFE IN BRITISH GUIANA 



J'iiotn hi/ /'. (!. U. 



FIG. 139. CELL OF BLUE HUNTRESS, OPENED TO SHOW COCOON 

 Enlarged two and one half times. 



dragging the unfortunate larva into death at the hands of 

 indigestion. 



Thus we see the reason for hard and fast rules among 

 insects. They are entirely dependent upon them for their 

 existence. Even so slight a variation as my experiment pro- 

 vided, proves this to my satisfaction. I varied the rules in 

 one small particular with the result that the larva was led 

 unconsciously to its own destruction. 



To go back : the larva upon finishing its spider, rests for 

 a short period before commencing its cocoon. This rest may 

 be necessary because there is nothing else to be done until 

 the spinning fluid of which the cocoon is to be made, com- 

 mences to flow. Once started, a network of strands is thrown 

 across the cell. They pass for the most part under the spin- 

 ner so that the grub rests upon a net, stretched midway be- 



