246 GREAT AUK. 



ve^ high, exceedingly compressed, tapering, and slightly declinate. Upper 

 mandible with the dorsal line straight for an inch and a quarter, then decli- 

 nate and decurvate to the end, the ridge very narrow, broader at the base; 

 the sides nearly flat, with a basal ridge succeeded by a deep groove, then a 

 large flat space, succeeded by eight oblique curved ridges, the edges sharp 

 toward the end, the tip decurved and obtuse. Nostrils marginal, linear, 

 short, pervious, but concealed by the feathers. Lower mandible with the 

 angle long, the sides extremely narrow and linear for half their length, the 

 horny part not being extended over the bone, which is covered with feathers, 

 afterwards deep and compressed, with the dorsal line at first convex, then 

 ascending and concave to the end, the sides flat, with about ten transverse 

 ridges, the edges sharp, the tip deflected. 



Head large, oblong, anteriorly narrowed. Eyes rather small. Neck 

 short and thick. Body compact and full. Wings extremely small, but per- 

 fectly formed. Feet placed far behind, short, very strong; tarsus short, 

 compressed, anteriorly scutellate, laterally covered with angular scales, those 

 on the hind part very small. Hind toe wanting; third toe longest, outer 

 nearly as long, inner much shorter, lateral toes marginate, all with numerous 

 scutella and several rows of angular scales above, and connected by reticu- 

 lated webs. Claws rather small, narrow, arched, convex above, and obtuse. 



Plumage close, blended, very soft, on the head and neck short and velvety. 

 Wings diminutive, much pointed; the primaries tapering to an acute point, 

 the first longest, the rest rapidly graduated, their coverts long; secondaries 

 short and broad, scarcely longer than their coverts. Tail short, pointed, of 

 fourteen feathers. 



Bill black, with the grooves between the transverse ridges white. Iris 

 hazel. Feet and claws black. Fore part of the neck below, and all the 

 lower parts white, of which colour also is a large oblong patch before each 

 eye and the tips of the secondary quills, the rest black; the throat and sides 

 of the neck tinged with chocolate-brown, the wings with greyish-brown, the 

 head, hind neck, and back glossed with olive-green. 



Length to end of tail 29 inches, to end of wings 23f, to end of claws 

 31^, to carpal joint 1S^; extent of wings 27i; wing from flexure 7-g-; tail 

 2^; bill along the ridge 3f, along the edge of lower mandible 4^; greatest 

 depth of upper mandible 1, depth of lower -|; width of gap 1^-; tarsus 2; 

 middle toe 2-f, its claw -§; outer toe 2-f, its claw |-*; inner toe 2f, its claw $. 



