GREAT AUK. 
129 
very 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 fea- 
thers, afterwards deep and compressed, with the dorsal line at first convex, 
then ascending and concave to the end, the sides flat, with about ten trans- 
verse 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 231, to end of claws 31i, 
to carpal joint 18£ ; extent of wings 2li ; wing from flexure ; tail 2f ; 
bill along the ridge 3i, along the edge of lower mandible 4£ ; greatest depth 
of upper mandible 1, depth of lower I ; width of gap 1^ ; tarsus 2 ; middle 
toe 2i, its claw £ ; outer toe 2f, its claw ® ; inner toe 2|, its claw 
Vol. VIII.— 17 
