82 HANDBOOK OF NATURE STUDY 



thorax united. If you look closely at the head of one of 

 your larger spiders, you will discover eight small eyes on it. 

 In front of the legs is a pair of organs which look like short 

 legs. They are called palpi, and are used by the spider in 

 handling its prey. The segments of the palpi next to the 

 head are flattened, and assist in chewing the food. In front 

 of the palpi are two strong jaws, each armed with a sharp 

 claw. Each claw has a small opening near its sharp point, 

 and when the spider bites, poison from a gland in the head 

 flows through this opening. The small insects which con- 

 stitute the spider's prey are quickly killed or benumbed by 

 this poison, but it has but little effect on the human skin. 

 There is no well-authenticated case on record where a person 

 was fatally poisoned by the bite of a spider ; but as some 

 persons are very susceptible to poisons, it is best to avoid 

 being bitten. 



Near the end of the abdomen, you can observe several 

 small, wart-like protuberances ; these are the spinnerets. 

 Each spinneret is provided with a few large and many 

 small openings ; out of these flows a soft, viscid substance, 

 which hardens as soon as it is exposed to the air. 



Structure of an orb weaver's net. Com stock in his 

 Manual says : " Few, if any, of the structures built by lower 

 animals are more wonderful than the nests of orb-weaving 

 spiders; but these beautiful objects are so common that 

 they are often considered hardly worthy of notice. If they 

 occurred only in some remote corner of the earth, every one 

 would read of them with interest.' 7 The spider first con- 

 structs a framework of dry and inelastic lines, which are 

 uniformly taut and quite strong. The outer part of the 

 framework is irregular, but the central part is regular and 

 consists of a number of lines which radiate from the centre 

 of the web. To these radiating lines the spider fastens a 

 thin, sticky, and elastic thread, usually in the form of 



