Department Circular 79, V. S. Dept. of Agriculture. 



ports it from Africa, China, India, Mauritius, Comoro Islands, 

 Bahamas, and South America. It is the common mite on fowls in 

 these countries, Dermanyssus gallinae De Geer not being found. He 

 reports it from fowls, the starling, the sparrow, a native bird of the 

 Comoro Islands called " hibon," and a single specimen from a lizard, 

 and states that it is reported to attack man. This mite has been taken 

 from fowls suffering from spirochaetosis, and Hirst thinks that it 

 transmits the disease. 



THE TROPICAL FOWL MITE AND THE COMMON ROOST MITE COMPARED. 



Liponyssus bursa, the trop- 

 ical fowl mite (fig. 1), is con- 

 siderably smaller than Der- 

 manyssus gallinae, the roost 

 mite, and it moves about 

 much faster. The posterior 

 end of the abdomen in the 

 female is bilobed in most 

 specimens. The hairs on the 

 dorsum are longer and more 

 prominent than in D. galli- 

 nae, and the legs are smaller. 

 Z. bursa is found in the nests 

 and on the fowls. D. gallinae 

 is found in cracks of the roost 

 and building, in nests, and 

 only sparsely on fowls. D. gallinae does not deposit eggs and mo it 

 on its host; Z. bursa does. D. gallinae feeds at night; Z. bursa may 

 feed both night and day. 



Fig. 1. — Tropical fowl mite ; Engorged speci 

 men. Greatly enlarged. 



LIFE HISTORY AT RAYMOND, ILL., MAY, 1919. 



The eggs of Z. bursa are laid either on the host or in the nest. 

 Large numbers of them are found in the fluff of the feathers. They 

 are not attached, but may adhere by means of a sticky substance. 

 They have been found also inside the straw from a nest. Off of the 

 host the eggs will hatch in 3 days. The minute larva does not feed, 

 but molts in about 17 hours. It is then ready to feed. The first- 

 stage nymph will molt in 1 to 2 days. The molting period of the 

 second-stage nymph was not determined. 



HABITS. 



While Dermanyssus gallinae has the habit of staying in and about 

 the roost most of the time and breeding there, Liponyssus bursa stays 

 cillier on its host or in the nest and breeds in both of these places. 

 None of these mites is found on the roost. In the case of the English 



