ALCID.E — FRATERCULINM: SEA PARROTS. 



1063 



Fig. 717. —Head of Sea Parrot (F. arctica), uat. size. (Ad. nat. del. E. C.) 



portions of both mandibles hard, horny, and persistent, depressed with several oblique curved 

 grooves, convex forward. Basal portion of upper mandible forming a narrow obtuse-angled 

 triangular space, or nasal fossa, its short base horizontal, its long sides rising and sloping 

 backward to meet at an acute angle at base of culmen ; nostrils linear, horizontal, close to 

 commissure at base of this space, which iu winter is naked and membranous, in summer cov- 

 ered with a sym- 

 metrical horny 

 '' saddle" sheath- 

 ing nasal fossa ; 

 with a raised 

 "collar" sur- 

 rounding base of 

 upper mandible, 

 through numer- 

 ous perforations 

 of which protrude 

 rudimentary 

 feathers ; with a 

 small narrow 

 horizontal horny 

 strip on each side 



below nostrils ; usually, also, with a long, narrow, obliquely vertical strip bounding the tri- 

 angular space anteriorly. Basal portion of under mandible contracted and membranous iu 

 winter, in summer with a symmetrical horny " shoe" which carries the line of the gonys down- 

 ward and backward to a point, and a narrow horny strip along base. These deciduous ele- 

 ments form 3 symmetrical pieces, surrounding the bill, and 3 or 2 pairs of lateral pieces; in all, 

 9 or 7 pieces (9 in arctica and glacialis, 7 in corniculatu) which are regularly moulted. Angle 

 of mouth with a rosette of naked skin, festooned in summer, shrunken in winter. Eyelids 

 surmounted above by a triangular, obtuse or acute, below by a horizontal, lengthened callosity. 

 No crests on head, but a furrow iu plumage behind eye. Wings not peculiar. Tail rounded, 

 but central feathers shorter than the next, contained about 2^ times in length of wing, 16- 

 feathered. Tarsus very short, only equal to inner toe without claw, stout, little compressed, 

 reticulate except for a small scutellate space in front. Outer toe about equal to middle; its 

 claw shorter than middle claw, both slightly curved, not very acute, upright ; middle claw 

 dilated on inner edge ; inner claw enlarged, curved to a semicircle, very acute, usually lying 

 horizontal. Sexes alike; seasonal changes of plumage slight, those connected with moult of 

 bill very great. Egg single, white or scarcely marked, laid in rocky crevices or burrows in 

 ground. Young in down sooty, with white belly. 



Analysis of Species and Subspecies. 



Excrescence of upper eyelid forming a slender acute horn. Height of bill much greater than length of commissure. 



Black of throat reaching bill. N. Pacific corniciilata 



Excrescence of upper eyelid forming an obtuse process. Black of throat not reaching bill. 



Culmen moderately convex, its chord about 2.0O; its arc 'J. 10; bill under 1.50 deep at base. Wing under 7.00. 



N. Atlantic arctica 



Culmen very convex, its chord about 2.40 ; its arc 2. CO ; bill over 1 50 deep at base. Wing 7.00 or more. Arctic 



arctica glacialis 



F. cornicula'ta. (Lat. cormcnlata, having a little horn (over the eye) ; corniciilum, a cor- 

 nicle, small horn; dimiu. of cornw, a horn. Figs. 718, 719.) HoRNED MASKING Puffin. 

 Adult (J 9 ) '" summer : Appendage of upper eyelid produced into a long, slender, acute, up- 

 right horn; tliat of lower eyelid linear, obtuse, horizontal, liill very large, especially higli for 

 its length, its height abttut equal to chord of culmen exclusive of tlie basal collar, much greater 



