359. 
. ALCIDA|— PHALERIDINZ: 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; tail 1.55; tarsus about 1.00; middle toe alone 1.10; : chord of culmen 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 cliffs 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, 2.25 to 2.35 long by 1.45 to 1.50. 
S. cristatel/lus. (Lat. cristatellus, dimin. of 
cristatus, crested. Figs. 540, 541,542.) CresTED 
Aux. Snus-nosep Aux. Bill fundamentally 
small and simple, compressed-conic, with convex 
culmen 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 I 
nasal fossa, separate from its fellow of the oppo- Fie. 540. — Crested Auk, reduced. (Ad. nat. del. 
ae . - -H. W. Elliott.) 
site side ; a subnasal strip prolonged on the cutting 
edge of the upper mandibles backward from the nostrils; a rosette-like 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 all which are 
moulted; all these elements vermilion or coral-red; end of the bill enamel-yellow. (Before 
acquiring these growths the young bird is tetraculus of authors; the adult in winter, after 
Fig. 541. — Crested Auk, in summer, nat. size. Fie. 542. — Crested Auk, in winter, nat. size. 
shedding them, is dubius.) A beautiful crest of 12-20 slender feathers springing from the fore- 
head, curling over forward in are of a circle to fall gracefully upon the bill; this helmet is 
blackish ; at full length about 2 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 
