COMMON FLEA. 



79 



possess, but as they are hardly perceptible the order 

 has from them been named Aphaniptera (" impercep- 

 tible- wmged "). The legs look as if they had two 

 extra joints above the thigh. The one that joins to 

 the thigh is a much enlarged form of the hip-joint, or 

 <:oxa, which hardly shows in the legs of many insects, 

 and therefore is a good anatomical example ; and 



Fig. G3. — Fiea : u.a^s^oi, and pupa, magnified. 



above it, joining the coxa, or hip, to the body, is a 

 prolonged growth from the lower part of it, giving the 

 appearance of the leg being formed of five joints. 



Fleas lay about ten or twenty eggs in hair of ani- 

 mals, or dusty nooks or crannies, &c., especially where 

 infested animals lie. From these eggs, white, worm- 

 like, footless grubs hatch, which feed on animal 

 matter, and notably on blood. In summer they change 

 their condition in about a fortnight, and, after casting 

 their skin, appear as chrysalids, resembling the per- 

 fect Flea, but inactive, and with the legs folded 

 beneath it. From these the Fleas are said to appear 

 in rather more or less than fourteen days. 



As a farm pest, I can say from personal observation 

 that these most unpleasant creatures sometimes 

 swarm in legions in neglected yards, where they may 

 be seen by scores skipping in all directions about the 

 haunts where nothing but dirt and neglect have allowed 

 them to be reared, although their presence will very 



