ARDEIDJ2 THE HERONS. 134* 



Nycticorax americanus BONAP. Comp. List. 1838, 48. 

 Nycticorax vulgaris D'OEB. Ois. Cuba, 1839, 208. 

 Nycticorax griseus (part) EEICHEN. J. f. 0. 1877, 237. 



HAS. The whole of temperate and tropical America, from British America to Chili and 

 the Falkland Islands. Part of the West Indies ; Bermudas. 



SP. CHAB. Adult: Pileum, scapulars, and interscapulars. glossy blackish bottle-green; 

 forehead, postocular, malar, and gular regions, and median lower parts, white; lateral lower 

 parts and neck, except in front, pale ash-gray, with a slight lilaceous tinge; wings, rump, 

 upper tail-coverts and tail, deeper ash-gray. Occipital plumes pure white. Bill black; 

 lores and orbits yellowish green; iris bright red; legs and feet yellow, claws brown. 

 (AuDUBON.) 1 Immature: Similar to the adult, but scapulars and interscapulars like the 

 wings, and the white of the forehead obscured by the blackish of the crown; the colors 

 generally more sombre, with neck and lower parts more decidedly ashy. Young: Above, 

 grayish brown, with more or less of a cinnamon cast, especially on the remiges, each 

 feather marked with a median tear-shaped or wedge-shaped stripe of white, the remises 

 with small white terminal spots; rectrices plain ash-gray. Sides of the head and neck, and 

 entire lower parts, striped longitudinally with grayish brown and dull white; chin and 

 throat plain white medially. Bill light apple-green, the upper half of the maxilla blackifh, 

 the mandible with a tinge of the same near the end; lores light apple-green; eyelids simi- 

 lar but lighter, more yellowish, their inner edge black; iris dark chrome-yellow or dull 

 orange; legs and feet light yellowish apple-green :Iclaws grayish horn-color. 2 



Length about 24,00-26.00; expanse, 44.00. Weight. 1 Ib. 14 oz. (AUDUBON). Wing. 11.00- 

 12-80; tail, 4.20-5.30; culmen, 2.80-3.10; depth of bill. .70. -85; tarsus, 3.10-3.40; middle toe, 

 2.65-3.10; bare portion of tibia. .90-1.4(V S 



SUBUENUS Nyctanassa STEJNEGER. 



Nyctherodius REICH. Syst. Av. 1852, p. xvi (nee Nycterodius MACGILLIV. 1842). Type, 



Ardea violacea LINN. 

 Nyctanassa STEJN. Proc. U. S. Nat. Mus. x, sig. 19, Aug. 3, 1887,295, foot-note. Same type. 



SUBGEN. CHAB. Medium-sized Herons, of short, thick build; the bill extremely thick 

 and stout, with both outlines strongly convex; the legs long and slender; the dorsal 

 plumes much elongated and very narrow, reaching beyond the tail ; the occiput (in adult) 

 with several extremely long, linear white feathers. 



Bill short and very stout, the culmen curved regularly from the base, the gonys de - 

 cidedly convex and very much ascending;* maxillary tomium almost perfectly straight 

 throughout, but appreciably concave anteriorly, with a barely perceptible convexity toward 

 the base; mandibular tomium nearly straight, but perceptibly concave anteriorly. 5 Mental 



1 A captive specimen had the iris and legs colored as follows, from the last of March 

 to June 30th, the only portion of the year when it was under observation: Iris, deep Chi- 

 nese orange; legs and feet uniform light buffy flesh-color or pale salmon, not very different 

 from the (evanescent) color of sides of neck, without the slightest tinge of olive or yellow. 



a From a specimen killed August 13, 1879, near Washington, D. C. 



3 Extremes of thirteen examples from North and Middle America. 



* The lower outline of the bill is, in fact, more decidedly convex than the upper. 



6 We find considerable variation among individual^ in respect to the outlines; thus, a 

 specimen (female adult, No. 2759, Mus. B. R.) from Illinois has the mandibular tomium ex- 

 actly straight to near the end, where it gradually ascends to the tip, thereby producing a 

 very slight subterminal concavity; in No. 2758, another adult female from the same locality, 

 it is decidedly convex in the middle portion; while in an adult male, from Mazatlan (No. 

 58811), it is decidedly concave at the same place so much so, in fact, that a space is left be- 

 tween it and the upper tomium, on each side, when the bill is closed'tight! These discrep- 

 ancies, however, do not affect the general form of the bill, which is eminently character- 

 istic. 



