98 



PARASITES OF THE DOMESTIC ANIMALS 



Family I. Gamasid^ 



Acarina (p. 94). — The gamasid mites. The mouth parts are ar- 

 ranged for piercing and sucking, maxillae fused into a tube, maxillary- 

 palps five-segmented and provided inwardly with secondary palps. 

 The legs have six segments, the tarsi terminating by two hooklets. 

 There are two stigmata located near the insertion of the posterior legs. 

 The cephalothorax and abdomen are fused into one body. The integu- 

 ment is of a leathery texture. Eyes are absent. 



Dermanyssus Galling 



Poultry mite; chicken "tick" (Fig. 63). Gamasidaa (p. 98).— Body 

 somewhat egg-shaped with larger end posterior, slightly flattened from 

 above to below. The lower half of the body is provided/with short, 



Fig. 63. — Dermanyssus gallinse: a, adult; b, tarsus; c, mouth- 

 parts; d and e, young — all enlarged (after Osborn, Bull. No. 5, Bureau 

 of Entomology, U.S. Dept. of Agr.) . 



well-separated bristles. The color is light gray with dark patches 

 showing through the skin; when engorged with blood the color is a 

 distinct red. The ovigerous female is rather less than 1 mm. in length. 



Occurrence and Habits. — The little poultry mite, found everywhere . 

 where chickens are kept, is one of the most persistent and injurious pests 

 that the poultry raiser has to contend with. Remaining in darkened 

 retreats about the henhouse during the daytime, these acari come forth 

 at night to swarm upon the fowls and suck their blood. Their attack, 

 however, is not confined entirely to the night, and hens may be driven 



