CHIONIS MINOR. 



91 



DESCRIPTION. 



The first specimen selected for examination was taken from alcohol 

 !N"ovember 5. The field-measurements, from the flesh, are as follows: — 



5 a 



% -- 

 3 ^ 



72 



a f^ 

 — ^ 



o 



'o 

 "a 



t« o 



p 



CO 







til 



'3 



S 



S 





c 



41 

 fcU 



§ 



Eemaiks. 





146 



1874. 

 Dec. 11 



? 



14.50 



39.00 



8.50 









1.75 



1.50 



0.50 



Preserved in alcohol. 









Plumage universally pure white, very soft and downy. Under plum- 

 age slate-colored. Bill black, stout, conical ; mandibles of equal length. 

 Chord of cnlmen 1.22, gape 1.35, depth 0.80, widl h 0.55 ; deptli of up- 

 per mandible 0.37, width 0.40 5 depth of lower mandible 0.30, width 

 0.55. Commissure nearly straight, with only a slight downward curve 

 towards apex of bill. Ljing over the upper mandible lilie a saddle, 

 with the i)ommel tilted up into the air, is the horny black sheath which 

 has given to this bird one of its trivial names. From the insertion ol 

 the frontal feathers to its anterior end, this sheath measures 0.50. The 

 llcips of the saddle project downward and backward below the tomial 

 line, its anterior margin presenting two curves, convex forward, includ- 

 ing one curve, convex posteriorly. The ''pommel" part of the sheath 

 projects above the mandible, like a hood, 0.20 inch. From gape to apex 

 the sheath measures 1.00; perpendicular depth 0.70, width of "pom- 

 mel" 0.30, of sheath between lower margin of flaps 0.45. At the sides 

 the flaps are firmly soldered to the upper mandible, so that, in this spe- 

 cies at least, erection of the sheath (attributed to (7. necrophaga or C. alba 

 by Latham, Lesson and Cuvier,*) is impossible. Structurally contin- 

 uous with the sheath, and extending backward and upward from its pos- 

 terior portion, is a thick, black, tumid strip of naked skin, deeply pitted 

 by numerous follicular openings, some of which near the edges give pas- 

 sage to hair-like feathers. It lies in contact with the eyelid superiorly, 

 and the portion uncovered by feathers measures 0.55 by 0.30. Upon 

 clipping away the frontal feathers, this black caruncle is found to ex- 

 tend entirely across the forehead, as a squarish frontal hood, covered by 

 white feathers so thickly as to be invisible in its anterior and central two- 

 thirds. Its upper margin (somewhat wider than the lower) is abruptly dis- 

 tinct, just opposite the highest part of the eyelid. The width of the carun- 

 cle at its upper and widest part is 1.10; its height from the lowest inser- 

 * Anitnal Kingdom, London, Orr & Co., 1849, p. 250. 



