126 ARTHROPODA 



found, and as none of the group make any noise they prob- 

 ably can not hear. 



The first pair of mouth appendages are the chelicerce, 

 terminating in claws at whose ends poison glands open. 

 The idea that thp bite of a spider which is made by the 

 chelicerse is dangerous, has no foundation in fact. In most 

 of our common species the terminal claw is scarcely long 

 enough to reach through the skin, and the poison is not 

 sufficient to cause any discomfort. Occasionally dirt 



FlG. 144. Agalena, the grass spider. At the right is a photograph of its webs as 

 seen on a dewy morning ; at the left the spider with its cocoon of eggs in the 

 overlapped leaf photographed natural size. 



getting access beneath the skin with the poison may cause 

 an inflammation. The large spiders of the South, the taran- 

 tulas, possess large fangs and enough poison to make their 

 victim quite sick. 



The second pair of mouth parts, looking like legs, are the 

 pedipalps. On the ventral side of the abdomen near its 

 stalk attachment to the cephalo-thorax may be seen a pair 

 or two of slits opening into the lung sacs. These consist 

 of small cavities across which hang about a dozen lamellse 



