FLEA

a name for blood-sucking insects regarded by entomologists as constituting a sub-order of the two winged flies (Diptera), termed Aphaniptera because the wings are inconspicuous scales. All the species more or le resemble the common flea (Pulex irritans). The body is laterally compre ed, and the mouth-parts are modified into piercing stylets and a suctorial proboscis. The flea is ret nark able for its agility, leaping to a surprising distance, and its bite is very troublesome. Eleven species of flea are known to spread the germs of plague, especially one (Xenopsylla cheopis) that is parasitic on rats. The sand-flea (Sarcopsylla pene trans), chigoe, or jigger of tropical America, is a serious pest, for its eggs are deposited in the feet of human beings, causing painful swellings.