CHAPTER I 



Introducing Spiders 



SPIDER PREVIEW 



HIS BOOK TREATS OF THE SPIDERS 



of the United States and Canada and is concerned almost wholly 

 with their habits and life histories, their morphology and peculiarities, 

 and also with their numbers and kinds. Most of us know something 

 about spiders, but few of us are aware of the vast numbers that 

 exist and of the great diversity in appearance and habits of the spin- 

 ning creatures. Yet even a limited acquaintance soon makes it evi- 

 dent that spiders in many ways far outshine insects and lesser 

 animals of much greater reputation. Thus it seems desirable that, 

 at the very outset, a few of the striking peculiarities of the maligned 

 spiders be enumerated. 



Insects have developed wings and on them have attained the most 

 exalted place among the arthropods. Although a wingless creature 

 of the earth and its plant cover, the spiderling can float its threads 

 on the breezes and fly through the air, often reaching tremendous 

 heights and sailing for long distances. This "ballooning" of spiders 

 has been instrumental in distributing them into new colonizing areas 

 at a rate not possible even for insects with their wings. The rigging 

 of ships two hundred miles from the nearest land has been showered 

 with tiny aeronauts riding on silken streamers. The spider can spin 

 a line one-millionth of an inch in thickness, but most of its single 

 lines are ten or twenty times as thick. This strand of silk is a line 

 of great elasticity that will stretch one-fifth its length before break- 

 ing, and of a tensile strength second only to fused quartz fibers. It 

 is a line of such fineness that it is impossible to duplicate; it serves 

 admirably as a marker in various surveying and laboratory instru- 

 ments. An inveterate spinner during all of its life, the spider uses 

 silk for so many different purposes that this material is the most 



