Bui. 553, U. S. Dept. of Agriculture. 
Plate I. 
The Chicken Mite (Dermanyssus gallinae). 
Upper left, eggs; upper center, larva, dorsal view; upper right, first-stage nymph before feeding; 
below, old roost showing spots of excrement. All much enlarged except the lower figure, which 
is somewhat reduced. (Original.) 
