ALCID^—PHALEBIBIN^: AUKS. 



807 



flanks sooty brownish-black, grayer below than above ; other under parts white ; lining of 

 wings dark. Feet dull greenish or yellowish, darker behind and below. Length about 9.00 ; 

 wing 5.40-5.75; fail 1.55«; .'t&rsus about 1.00; middle toe alone 1.10; chord of eulmen or 

 gonys 0.60 ; gape 1.00 ; depth of bill 0.45 ; width 0.30. Young : No white filamentous feath- 

 ers on head ; a white spot on lower eyelid; upper ^^ 

 parts as before, under parts white, marbled and 

 mottled with dusky ends of the feathers. N. 

 Pacific and polar seas, highly arctic, apparently 

 not coming much south. This quaintly-beaked 

 bird resorts to clifl's and crags to breed, laying its 

 single egg deep in the cavities of the most inac- 

 cessible rocks overhanging the sea ; it resembles 

 a small narrow hen's egg, being white, variously 

 soiled and discolored, minutely granular and rough 

 to the touch, 3.35 to 2.35 long by 1.45 to 1.50. 

 M9. S. cristatel'lus. (Lat. cristateUus, dimin. of 

 cristatus, crested. Figs. 540, 541, 543.) Crested 

 Auk. Snub-nosed Auk. Bill fundamentally 

 small and simple, compressed-conic, with convex 

 eulmen and little sinuate horizontal commissure ; 

 but in the breeding season developing several 

 corneous appendages, which alter its shape great- 

 ly, make it singularly irregular, and modify even 

 the outline of the feathers at its base. These 

 accessory pieces are : a nasal plate, filling the 

 nasal fossa, separate from its fellow of the oppo- 

 site side ; a subnasal strip prolonged on the cutting 

 edge of the upper mandibles backward from the nostrils; a rosette-Uke plate at base of upper 

 mandible just over angle of the mouth ; a large shoe encasing the posterior part of the under 

 mandible ; the latter single, the other three pieces in pairs, making seven in aU which are 

 moulted ; all these elements vermilion or coral-red ; end of the bill enamel-yellow. (Before 

 acquiring these growths the young bird is tetroimlus of authors ; the adult in winter, after 



Fig. 540. — Crested Auk, reduced. (Ad. nat. del. 

 H. W. ElUott.) 



Fig. S41. — CrsBted Auk, in summer, nat. size. 



Fia, 542. —Crested Auk, in winter, nat. size. 



shedding them, is dmbvus.') A beautifal crest of 13-20 slender feathers springing from the fore- 

 head, curling over forward in arc of a circle to fall gracefaUy upon the bOl ; this helmet is 

 blackish ; at fuU length about 3 inches long ; the feathers are not filamentous, but have well- 

 formed webs, and are bundled or impacted together, owing to the oblique divergence of the 



