INSECT TROGLODYTES. 135 



i"eady refuge by running into its stronghold. The 

 object of the cliimuey is less apparent. It probably 

 serves as a watch-tower from which the keeper may 

 observe the aijproach of her enemies and her prey. 

 Her favorite position is a crouching posture on the 

 summit of her turret, with legs drawn up and head 

 peering over the edge as though on guard. A little 

 elevation of this sort is a great temptation to grass- 

 hoppers and other insects, who are prone to alight upon 

 or crawl up it, and thus become easy victims to the 

 vigilant tower-keeper. On the other hand, if anything 

 approaches that threatens harm, the wary sentinel re- 

 treats to the depths of her cavern. I suppose that the 

 turret serves a further use in protecting the interior 

 from being flooded by the water that gathers upon the 

 surface after rain."" 



" Have you any knowledge of the mode of building 

 practiced by this little architect ?" 



" Yes, I have kept individuals in confinement and 

 watched their habits, but the best account of their 

 l)ehavior has been given by my friend, INIrs. Mary Treat. 

 When the burrow is about two inches deep the spider 

 begins upon her tower. A stick is placed at the edge 

 of the tube, and lashed down with a strong thread. 

 Another is laid in similar position until the margin is 

 surrounded ijy a four or five-sided foundation. The 

 builder then descends to the bottom of her tube and 

 brings up pellets of earth which she places atop, and 

 on the inside of the sticks, pressing them down with her 

 body as she passes around the circle. Then follow 



