660 U. S. p. K. K. EXP. AND SURVEYS — ZOOLOGY GENERAL REPORT. 



C. Nycticoraceae. — Bill thick and stout, scarcely longer ttan head. Upper outlinede curved 

 from hase. Legs short, stout. Tarsi stout, short, nearly as long or a littlelonger than the 

 middle teo ; the scutellation with a tendency to become hexagonal anteriorly .Lateral toes 

 nearly equal, outer rather the longer. Claws short, much curved. Lower fourth of tibia bare. 

 Head with much elongated occipital feathers. No dorsal plumes. Neck short ; bare inferiorly 

 behind. Tail of twelve stiff feathers. 



Bdtorides. — Bill small, rather slender, gently curved. Gonys straight, but 

 ascending. Tarsus shorter than middle toe. No very long occipital plumes. 

 Nyctiardea. — Large. Bill very stout ; lower outline straight ; gonys slightly 

 concave. Tarsus about equal to middle toe. Occiput with an elongated plume. 

 Scapulars not longer than the tertials. 

 Nyctherodius. — Large. Bill stoutest and shortest of North American herons ; 

 inferior outline convex and curving as much as the superior. Tarsus decidedly 

 longer than the middle toe. Occiput with several much elongated feathers. 

 Scapulars reaching the tip of tail. 



DEMIEGRETTA, Blyth. 



Demiegrelta, " Blyth, 184-," perliaps described in Catalogue of Calcutta Museum, 280. Type Jlrdea jtigularis, Bljtb. 

 Herodias, Bonaparte, Consp. II, 1855, 120. Not of Boie, which has Jlrdea egretta for type. 



Cu. — Bill narrow, slender ; both outlines rather concave to the terminal half, then uniformly conve.x. Tarsi very long, 

 broadly scutellate ; toes very short ; the middle scarcely more than half the tarsus ; outer longest. Claws much curved, very 

 short and blunt. 



Back of neck well feathered. Head with a full occipital crest of elongated lanceolate feathers ; the tip of all the neck 

 feathers similar, as well as those on the lower part of the throat. Back with free fastigiate plumes longer than the tail. 



This genus is one of the most strongly marked among the entire family of herons, and in 

 some respects exhibits a near approach to the cranes. The well defined lanceolate feathers and 

 the short toes are quite peculiar features. 



There are three species belonging to the United States, which may be readily distinguished 

 as follows : 



Plumage pure white. Bill flesh colored at the base, the terminal half abruptly black. ..B. pealeii^ 



Head and neck (even on the throat) uniform reddish brown tinged with lilac. Body generally 

 grayish blue, paler beneath D. ru/a. 



Head, neck, and exposed upper 2)arts slaty blue. Chin and central line of throat, with the 

 under parts generally and rumj), white B. ludoviciana, 



I cannot determine satisfactorily what this genus should be called. It is not Herodias, as 

 stated by Bonaparte, since Boie's name was based upon the Ardea egretta of Linnaeus, and 

 consequently anticipates Egretta of Bonaparte. The only name I can find which has any 

 reference to the group is IJemiegreiia of Blyth, with his Ardea jugularis^ as the type. I 

 therefore adopt it, but with a strong suspicion that the American birds, with Ardea ludoviciana 

 as type, are entitled to a new generic appellation, for which Hydranassa would be exceedingly 

 appropriate. 



' Jlrdea jugularis, Blttii, Notes on the Fauna of Nicobar Islands, Jour. As. Soc. XV, 1846, 376. — Herodias concolor, Bon. 

 Conspectus, II, 1855, 121. 



