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FAMILY XXXL— PERDICINiE. PARTRIDGES. 



Bill very short, stout, broader than high at the base, with the upper man- 

 dible convex, thin-edged, obtuse, the lower with the dorsal line convex, the 

 tip rounded. Head small, oblong; neck of moderate length, or rather short; 

 body very bulky. Feet rather of moderate length, stout; tarsus bare, ante- 

 riorly scutellate; hind toe rather small, third long, lateral nearly equal, all 

 scutellate, anterior webbed at the base. Claws moderate, arched, compressed, 

 obtuse. Plumage full and strong; feathers with the plumule much developed. 

 Wings rather short, convex, rounded. Tail generally short and rounded, of 

 more than twelve feathers. Tongue triangular, pointed; oesophagus with a 

 very large crop; stomach a very strong muscular gizzard, with the lateral 

 muscles highly developed, the epithelium dense, with two concave grinding 

 surfaces; intestine long, and of moderate width; coeca very large, oblong, 

 internally with reticulate ridges. Trachea without inferior laryngeal muscles. 

 Nest on the ground, rudely constructed. Eggs numerous. Young covered 

 with stiffish down. 



Genus I.— ORTHYX, Steph. AMERICAN PARTRIDGE. 



Bill very short, robust, rather obtuse; upper mandible with the outline 

 decurved from the base, the ridge narrow at the base, on account of the 

 breadth of the nasal membrane, somewhat distinct in its whole length, with 

 the sides convex, the gap-line arched, the edges thin, without notch, the tip 

 decurved, thin-edged, obtuse; lower mandible with the angle short and 

 rounded, the dorsal line slightly convex, the sides rounded, the edges invo- 

 lute, the tip rounded. Nostrils basal, linear, operculate, nearly concealed. 

 Head of ordinary size, ovato-oblong; neck rather short; body full. Feet of 

 moderate length; tarsus shorter than the middle toe, with two anterior series 

 of large scales; first toe small and elevated; third very long, second shorter 

 than third, scutellate, connected at the base by webs of a considerable extent. 

 Claws rather stout, arched, compressed, rather acute. Plumage dense, rather 



