The unfortunate prejudice that exists against spiders in general is probably 

 due to fear of tarantulas and to ignorance of their nature and habits. Wherever 

 their presence and their webs are not objectionable, the spiders should be left 

 undisturbed to play their part in destroying insects and other undesirable small 

 organisms. 



KEY TO THE ORDERS OF ARACHNIDA 



1. Microscopic aquatic animals; legs without distinct segments; last pair of 



legs projecting from the posterior end of the body; (often grouped as 

 a class by many writers) 



Tardigrada Water Bears 

 Not usually microscopic; aquatic or terrestrial; legs segmented and on 

 sides of body 2. 



2. Abdomen unsegmented 3. 

 Abdomen segmented (sometimes evident only on under side) 4. 



3. Cephalothorax divided from the abdomen by a deep constriction through 



the middle of the body; with four pairs of legs 



Araneida or Araneae Spiders and Tarantulas 

 Head and thorax not distinct from the abdomen; with two or four pairs 

 of legs in the adult; usually with three pairs of legs in the young 



Acarina Mites, Ticks etc. 



4. With a tail-like projection from the end of the abdomen 5. 

 Abdomen without any taiMike projection 7. 



5. With a sting; first pair of legs shorter than the rest 



Scorpionida Scorpions 

 No sting; first pair of legs longer than the rest 6. 



6. Tail-like portion with bristles 



Palp}gradi or Microthely phonida Microscorpions 

 Tail -like portion smooth 



Pedipalpi, Families Shizonotidae and Thelyphonidae Tailed 

 Whip-scorpions 



7. Sides of animal outcurved or straight; pedipalps (second pair of mouth 



appendages) with or without opposing claws 8. 



With a constriction between head and thorax or between thorax and 



abdomen; no opposing claws on pedipalps 9. 



8. With opposing claws on pedipalps; animal long and narrow, wider pos- 



teriorly; legs moderate 



Chelonethida or Pseudoscorpwnida False Scorpions 

 No opposing claws on pedipalps; animal ovoid; legs extremely long and 

 slender 



Phalangnda Harvestmen or Daddy-long-legs 



9. Head constricted from thorax; body not flattened 



Solpugida Solpugids 

 With a narrow constriction between the cephalothorax and the abdomen; 

 body broad and flat 



Pedipalpi, Family TarantuUdae or Phrynidae 

 Tailless Whip-scorpions (Not Tarantulas) 



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