26 AMERICAN SPIDKRS AND THEIR SPINNINGWORK. 



tube, always with its back to the glass, a'nd adjusted its fore feet so that 

 the tips touched beneath and partly behind the ball of earth. Then with 

 a sudden movement, like snapping the fingers, she shot the earth forth with 

 sufficient force to make it hit the opposite side of the jar. These pellets 

 were held together with a kind of mucilage, sometimes mixed with web 

 lines, showing that in massing the pellets preparatory to deporting them, 

 probably some secretion from the salivary glands is used, and that occa- 

 sionally filaments of thread are also utilized for binding the particles of 

 earth together. 1 



A Turret spider was kept in confinement by Mrs. Treat and furnished 

 with sticks and moss in order to observe the manner of erecting her tower. 

 When she had carried down her burrow about two inches in 

 depth she commenced to build the tower above it. She would 

 Building * a ' ce ^ ne s ^ c ^ s f rom * ne lady's fingers and place them at the 

 edge of her tube. She worked while inside her burrow, holding 

 the stick with her forefingers until it was arranged to suit her. She then 

 turned and fastened it with a strong web. She took another stick, pro- 

 ceeded in the same way, and continued thus until she had laid the foun- 

 dation of a five sided wall. 



Next she went to the bottom of the tube and brought up a pellet of 



earth which she placed at the top of the sticks, and proceeding thus erected 



a circle of pellets which she next overspun. They were so arranged as to 



cover the sticks on the inside, leaving the inner walls perfectly rounded and 



silk lined. Then the spider was ready for more sticks, which she continued 



to alternate witlj pellets until the tower reached a height two-and-one-half 



inches above the burrow. Sometimes bits of moss an inch or two in length 



were given her by the observer, which were used by fastening them to a stick 



with threads of silk. This made a wall fringed on the outside with moss. 



If the spider were not in a mood for building, and a stick were offered 



her she would take it in her mandibles, and with her fore feet give it a 



quick blow, often sending it away with force enough to hit the 



lingmg enclosing jar. When she was digging and bringing up pellets of 



earth which she did not wish to use upon her tower, she would 



throw these from the top of the walls with sufficient force to send 



them a foot or more from the burrow, had it not been for the intervening 



glass. This habit accounts for the fact that the observer could never find 



fresh earth near the burrows of Turret spiders. 



What motive could the aranead have for thus casting the fresh earth 

 away from the immediate vicinity of her nest ? No doubt, had the soil 

 been permitted to accumulate by dumping it directly from the tower, the 

 protective uses of the tower would thus have been destroyed. Can it be, 

 moreover, that the secretive instinct which is observed in the building 



1 Harper's Magazine, 1880, page 862. 



