250 NATURE-STUDY 



the silk threads issue. This consists of a number of little 

 projections covered with minute, tubular hairs, through which 

 the threads come. The silk is at first liquid, but quickly 

 hardens in the air. The different strands are pressed and 

 twisted together into a strong thread. The spider uses its 



hind feet in arranging, 

 guiding, and fastening its 

 silk. 



Shake a spider from its 

 web. Notice that it is 

 still attached to the web 

 by a fine thread upon 

 which it again climbs 

 back. 



Spiders are useful crea- 

 tures and destroy many 



FIG. 94. Spinneret. . 



insects. Out of doors 



they ought to be protected rather than killed. Try to 

 counteract the prevailing prejudice against them. 



Related to spiders are the Daddy-long-legs, or Harvestmen, 

 which also are useful in destroying mosquitoes and other 

 insects. 



Centipedes and Millipedes possess the segmental character 

 of the body, the jointed legs, and the biting mouth-parts of 

 insects, yet are very different. They are found under /boards, 

 logs, and stones. Centipedes are flat, worm-like animals, with 

 a pair of legs to each joint of the body. They are carniv- 

 orous, living on other insects, worms, etc., which they catch. 

 The first pair of feet are modified into poison fangs. In 

 tropical countries there are large centipedes whose bite is 

 dangerous to man. Similar to the last is the millipede, or 



