131 



LIFE HISTORY. 



The development of this species resembles that, already known, 

 of other common fleas. The earlier writers on the hen tiea sup- 

 posed that eggs might be retained and hatched within the body 

 of the parent, as is the habit of the Jigger Flea (Sarcopsylla 

 penetrans L. ), of the Southern States. We have been able to 

 trace through the entire life cycle, and hence can work more in- 

 telligently in combating them. 



The female fleas remain attached after they have found a suit- 

 able host, the eggs being dropped as fast as they are produced. 

 Evidently the egg laying goes on very rapidly at night, for the 

 roosting board, under infested fowls, is always thickly covered 

 with them, in the morning. The eggs are very small, of course, 

 and resemble small white specks, just visible to the naked eye. 

 With a lens they appear as beautiful, pearly white, oval objects. 

 about one-third longer than wide. Fleas removed from the hens 

 and placed in vials j^roduced eggs at once; using these, the incu- 

 bation period was easilv determined — the vtnmg hatching in 

 3y'2 to 4 days. 



Some difficulty was at first experienced in feeding the larvae, 

 until it was discovered that they, too, like other common species, 

 live on dried blood particles in the dust. Examining the attached 

 fleas, the writer saw that the blood of the fowl was rapidly pass- 

 ing through them, and being dropped in the form of small coagu 

 lated pellets. It had already been noticed that the food in the 

 stomach of the larvae, collected on the roosting board, showed 

 through the skin, a dark-red color, and the literature on other 

 species indicated that they possibly feed upon this excrement of 

 the parents. In the test tubes containing these dry pellets of 

 blood, mixed with the dust, the fleas were easily reared to their 

 adult stage. 



The larva is a small, wormlike creature, and even when fully 

 developed is only about 3 mm. in length. Normally, they are 

 covered up in the dust, but if thev are stirred up, and placed on 

 top. they quickly wrigiile in again. When ready to juipate the 

 larva^e become pearly white, with the alimentary canal empty 

 and the body stored with fat. The larval period was found to 

 vary considerably — lasting from 6 to 10 days. When ready to 

 pupate the larva spins a delicate cocoon, of the finest silk, which 

 holds the particles of dust together, about it. Often the cocoons 

 were made against the side of the glass tube, so that one could 

 see through and note the transformation inside. After building 

 the cocoon the larva rests from 3 to 4 days, doubled up inside, 

 before pupating. The pupal stage lasts from 6 to 9 days ; the pupa 

 beginning to turn dark several days before emerging. Thus the 

 entire life cycle from egg to the adult fleas takes from 3 to 4 

 weeks. 



