AEDEIU^— THE HERONS. 134* 



Mycticorax americanus Bonap. Oomp. List, 1838, <8. 

 Nyoticorax vulgaris D'Obb. 01s. Cuba, 1839, 208. 

 Nyctioorax griseus (part) Bbiohbn. J. f . 0. 1877, 237. 



Hab. 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: Fileum, 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 lilaceons tinge; wings, rump, 

 upper tail-ooverts 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.)i 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, especiaJiy on the remlges, each 

 feather markedwith a median tear-shaped or wedge-shaped stripe of white, the remires 

 with small white terminal spots ; rectrioes plain ash-gray. Bides 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 blackish, 

 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 ;rclaws grayish horn-color.' 



Length about 24.00-26.00; expanse, 44.00. Weight. 1 lb. 14 oz. (Audubon). Wing. 11.00- 

 12-80; tail, 4.20^.30; qulmen, 2.80-3.10; depth ot bill, .79.-85; tarsus. S.10-S.40; middle toe, 

 2.55-3.10; bare portion of tibia. . 90-1.40." 



Subgenus Nyctanassa Stejnegeg. 



Nyctherodius Reioh. Syst. At. 1852, p. ivl (.nee Nycterodius Maogilliv. 1842). Type, 



Ardea violaoeajASTS. 

 Nyetanassa Stejn. Froc. U. S. Nat. Uus.x,sig. 19, Aug. 3, 1887,295, foot-note. Same type. 



Sdbgbn. 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 oulmen 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 .» Mental 



' 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. 



« From a specimen killed August IS, 1879, near Washington, B.C. 



» Extremes of thirteen examples from North and Middle America. 



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



5 We find cohsiderable variation among individuals in respect to the outlines; thus, a 

 specimen (female adult. No. 2759, Mus. E. B.) 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- 

 tweeij it and the upper tomium, on each side, when the bill is closed tight I These disorep- 

 anoies, however, do not aSeot the general form of the bill, which is eminently charaeter- 

 istio. 



