INIarch 1896.] 



PARASITES OF POULTRY. 



421 



(1.) Fleas (Pulicidce). — The ileas, which are true insects, 

 belong to the order of flies (Diptera). They live upon the blood 

 of animals. One species only lives upon the fowl, namely, the 

 bird flea (Pulex gcdlince or avium), which attacks also most 

 other birds. The hen flea, as it is generally called, is abundant 

 in dirty fowl runs, and especially in the nests where straw 

 is used. The adult flea is dark in colour, and, as in all 

 fleas, is devoid of wings. The fleas are provided with very 

 sharp piercing mouths, their food consisting almost entirely of 

 blood. They are not often seen on the fowls, hence little notice 

 is taken of them. They are what are termed " partial para- 

 sites " — parasites that only go to their hosts to feed. The fleas 

 are not noticed on the birds because they generally attack them 

 at night ; then, however, they do much harm, causing constant 

 irritation and loss of blood, and depriving them of rest. 



Life-history of Hen Flea. — The female flea lays lier eggs 

 (nits) chiePiy in the nests amongst dust and dirt and in the 

 crevices of the walls and floor. The^e nits give rise to pearly 

 white maggots, with brown horny heads, which can often be 

 found in the bottom of the nests amongst the dust (Fig. 1). 



Fig. 1. 



Larva of hen flea (greatly enlarged) . 



These larvse are mature in two or three weeks, when they reach 

 about one-sixth of an inch in length. In warm weather they 

 may be full fed in even ten days. They then spin a pale 

 cocoon amongst the dirt, in which they pupate. The pupa 



Fig. 2. 



r 



Pupa of hen flea (greatly enlarged). 



(Fig. 2) is at tirst pale brown, then dark chestnut brown. In 

 this condition the flea remains ten to twenty-one days, when 

 the pupa hatches into the adult. They breed all the year round, 

 but chiefly in warm weather. It is well to remember that, 

 whenever there are dark and dirty hen roosts, there are sure to 

 be numbers of Pidex gallince. 



