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The Orders of Insects 



Sub-Order A. Aphaniptera. 



The Aphaniptera or Fleas are characterised by 

 the entire absence of wings, and the flattening of their 

 bodies from side to side. The feelers are short and 

 usually hidden in pits on either side of the head; they 

 seem to have four segments, but the last is ringed 

 and really represents a number of segments fused 



Fig. 143. — c. Common Flea (Pulex irritans, Linn.), 

 Europe, etc. ; a. larva ; b. pupa. Magnified. From 

 Osborn, Bull. 5 (n.s.), Div. Ent. U.S. Dept. Agr. 



together. The only eyes are a few simple ocelli. 

 The jaws are powerful, piercing organs, the mandibles 

 and hypopharynx being developed as hard toothed 

 stylets; the palps of both pairs of maxillae are present. 

 The legs are long and powerful, owing to the great 

 size of the haunches, specially adapted for leaping. 

 The larvae are soft white grubs with well-chitinised 



