494 



JOURXAL OF ECOXO^IIC EXTOMOLOGY 



r^'oi. 8 



emerged fleas that were confined for many days in vials and jars 

 witiiout feeding, were not observed to mate and in no case were eggs 

 produced. 



Female fleas removed from fowls and placed in empty vials oviposit 

 at once — from one to three eggs being produced. These fleas, if left 

 in the A'ials. usually died during the following day. 



Egg-production appears to depend largely upon the proximity of the 

 males. The first and second day after mating the maximum number 

 of eggs are produced: and, from that time on the number rapidly falls 

 ofi' until mating takes place again. Often females, that were not 

 kept supplied with males, produced eggs which dried up quickly. 

 By placing fresh males on the rooster's head from time to time, it 

 was found that the females reproduced actively throughout their hfe. 



The Eggs. — The eggs are laid singly, and, being dry. they rolled 

 about in the capsules, so that it was rather difficult to keep them from 

 falling out. They are oval in form, about one third longer than wide, 

 and a beautiful opalescent white. 



Since the eggs are largely produced at night, they may be found 

 abundantlj^ on the roosting-board of infested fowls. 



The Larv^.— The incubation period was found to vary from three 

 and one-half to four days, at ordinary summer temperature. Eggs 

 kept under observation during hatching became yellowish: and by 

 transmitted light the larva could be plainly distinguished within. 

 By a jerking motion of the bod}', the hatching spine, which is located 

 on the top of the head of the larva, was observed effectively making 

 a single slit in the egg-shell; through which the larva escaped. 



The newly-hatched larvae are quite white and very active, wrigghng 

 about over the surface of the soil. Within a few hours, if kept under 

 natural conditions, they turn dark, due to the food within the alimen- 

 tary canal. As was mentioned above, the parent fleas are constantly 

 producing pellets of dried blood, which fall with the eggs to the soil. 

 The larvae apparently feed upon this excrement exclusively. 



The larvae were found to molt three times — the hatching-spine 

 disappeared at the first molt. The older larvae burrow into the soil so 

 that they were always found at the bottom of the jars in the experi- 

 ments. T\'hen ready to pupate the food all leaves the alimentar}' canal 

 and the larvae become pearly-white again. The larval period was 

 found to vary considerably — lasting from six to ten days at summer 

 temperature. 



The Pupa. — When ready to pupate the larva spins a dehcate cocoon, 

 of the finest silk, which holds the particles of dust together around it. 

 In most cases these cocoons were made against the glass, at the bottom 

 of the breeding jars, so that the transformations could be observed 

 through the wall. 



