AUKS AND ALLIED SPECIES. 311 



1. Utamania Tarda . Common Razor-hiU. T>ill black, 

 Avitli four transverse grooves, one of whicli is white. 



GENUS IV. ALCA. AUK. 



Bill longer than the head, very high, much compressed, 

 with the outline of the upper mandible areuato-decurvate, the 

 sides nearly flat and erect, with numerous transverse grooves, 

 the edges inflected and sharp ; tarsus very short, stout, com- 

 pressed ; toes of moderate length, the outer slightly shorter 

 than the middle toe ; claws rather small, arched, compressed, 

 rather obtuse ; wings extremely small, much pointed ; tail 

 short, pointed, of fourteen feathers. 



1. Alca hnpennis. Great Auk. Length about a foot 

 and a half. 



GENUS V. MORMON. PUFFIN. 



Bill about the length of the head, nearly as high as long, 

 extremely compressed, obliquely grooved on the sides ; nos- 

 trils linear, marginal ; tarsus very short, little compressed, 

 scutellate ; outer and middle toes about equal ; claws strong, 

 arched, acute, that of the inner toe hooked ; wings short, 

 narrow, much curved, acute ; tail very short, slightly rounded, 

 of sixteen feathers. 



1. Mormon arcticus. Arctic Puffin. Bill with three 

 curved furrows on each mandible ; the basal rim and first 

 ridge of both mandibles dull yellow, the intervening broad 

 space greyish-blue, the rest bright red ; a flattened triangular 

 horny body on the upper eyelid, and an elongated adherent 

 plate on the lower. 



