THE SPIDER AND ITS ALLIES 83 



bound up, either for immediate or future consumption. A 

 few authentic instances have been recorded of the capture 

 of mice by ordinary spiders, and some tropical o o o 

 spiders are said to capture occasionally small 

 birds within their Avebs. All spiders eat FIG. so. Dia- 



, ,. . , . , gram of posi- 



voraciously, and ordinarily drink a great thmof eyesm 

 deal of water; yet they may survive, in Theridium. 



J J The four cen- 



the absence of food and water, for many trai eyes are 

 months. the lar s est - 



Distribution. Argiope occurs over all of North America. 

 A. cophinaria, the basket Argiope, is the large black and 

 yellow spider well known to all frequenters of fields. It 

 occurs from Massachusetts to Texas, and west to the Pacific 

 coast. A. argentata, distinguished by the serrated form of 

 the abdomen, is found in the Southern States, the West 

 Indies, and northern South America. Theridium occurs 

 all over the world. T. tepidariorum is found, outside of the 

 United States, in South America, Europe, and Australia. 

 Twelve other species of this genus are found in New 

 England alone. Some of these spin webs in trees or 

 bushes, others in stone walls or among rocks. 



Spinning Habits. Spiders spin for a variety of purposes. 

 Cocoons are made of silk, for the protection of eggs ; under- 

 ground nests, like that of the trap-door spider, are lined 

 with silk ; and, especially, nets are made of it to ensnare 

 insects. The silky threads may serve also to suspend the 

 spider while it drops from a tree, or they may, by their 

 friction with the air, serve to suspend certain spiders in 

 aerial migrations. 1 This latter use is especially noteworthy. 



1 The ballooning habit of spiders has been noticed since early times, 

 but it was formerly misinterpreted. Thus Pliny speaks of wool being 

 rained. The poet Spenser wrote : 



