262 MANUAL OF NATURAL HISTORY. 



sometimes ingeniously tested by making them draw 

 miniature carriages, &c., and by the wonderful agi- 

 lity they display, often exciting the extreme wrath 

 of him who desires to prevent them from enjoying a 

 carousal off his blood. The common Flea (Pulex 

 irritans) is produced from a small white polished 

 egg ; the larvae are without feet, and beset with 

 hairs, the head has short antennae, and there is a 

 pair of curved forks at the end of the tail. When 

 the larva is full-grown, it casts its skin, becomes a 

 grub or pupa ; from which, in twelve days, the per- 

 fect insect emerges, with its sharp proboscis, and its 

 shelly armour. Another troublesome insect be- 

 longing to this Order, is the Chigoe or Jigger 

 (Sarcopsylla penetrans), a small black flea, which 

 penetrates the flesh, and, if neglected, produces 

 troublesome sores on the feet. A very large species 

 of flea is found on the Mole; another species, of 

 yet larger dimensions (Pulex Echidnce), is found on 

 the Australian-Porcupine ; but perhaps the largest 

 known is the Pulex gigas, from some northern 

 animal. 



XII. ORDER FLEAS (Aphaniptera). 



Wings four, rudimentary, in form of small scaly 

 plates on sides of body ; antennas minute, lying flat 

 in cavities at sides of head ; mouth formed for suc- 

 tion ; mandibles and lingua setiform ; body com- 

 pressed ; tarsi 5-jointed. Larva vermiform ; pupa 

 inactive, incomplete. 

 1. FAMILY Fleas (Pulicidae). Head small ; mouth 



