134 



ANIMAL FORMS 



parasites or as active predaceous animals upon other animals. 

 For this purpose many are provided with keen senses for 

 detecting their prey and poisonous spines for despatching it. 

 129. The scorpions. Owing to the stout investing armor, 

 the strong pincers, and the general form of the body, the 

 scorpions might at first sight be mistaken for near relatives 



of the crayfish or lobster. 

 A more careful examina- 

 tion will show that the 

 two pairs of pincers prob- 

 ably correspond to the 

 antennae and mandibles of 

 the Crustacea that have 

 become modified for seiz- 

 ing the food. The swol- 

 len part of the animal 

 lying behind the four 

 pairs of legs is a part of 

 the abdomen, of which 

 the slender " tail " consti- 

 tutes the remainder. On 

 the tip of the tail is a 

 curved spine supplied 

 with poison glands. Sev- 

 eral pairs of eyes are borne 

 on the dorsal surface of 

 the head and thorax, while 

 on the under side of the animal several slit-like openings 

 lead into as many small cavities containing the lung-books. 

 The scorpions are the inhabitants of warm countries, 

 where they may be found under sticks and stones through- 

 out the day. At night they leave their homes in search of 

 food, which consists chiefly of insects and spiders. These 

 are seized by means of the pincers, and the sting is driven 

 into them with speedily fatal results. It is doubtful if the 

 poison causes death in man, but the sting of some of the 



'.Scorpion, showing pincer-like mouth- 

 parts and spine-tipped tail. 



