660 
U. S. P. E. E. EXP. AND SUEVEYS ZOOLOGY GENEEAL EEPOET. 
0. Nycticoraceae. — Bill thick and stout, scarcely longer than 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 hecome hexagonal anteriorly .Lateral toes 
nearly equal, outer rather the longer. Claws short, much curved. Lower fourth of tibia hare. 
Head with much elongated occipital feathers. No dorsal plumes. Neck short ; bare inferiorly 
behind. Tail of twelve stiff feathers. 
Butorides. — 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 superiDr. Tarsus decidedly 
longer than the middle toe. Occiput with several much elongated feathers. 
Scapulars reaching the tip of tail. 
DEMIEGRETTA, Blyth. 
Dcmiegretta, " Bltth, 184— , " perhaps described in Catalogue of Calcutta Museum, 280. Typo Jlrdea jugularis, Blyth. 
Ilerodias, Bonaparte, Consp. II, 1855, 120. Not of Boie, which has Ardea egretta for type. 
Ch. — Bill narrow, slender ; both outlines rather concave to the terminal half, then uniformly convex. Tarsi very long, 
broadly seutellate ; 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 fastigiato 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. ..D. pealeii w 
Plead and neck (even on the throat) uniform reddish brown tinged with lilac. Body generally 
grayish blue, paler beneath D. rufa. 
Head, neck, and exposed upper parts slaty blue. Chin and central line of throat, with the 
under parts generally and rump, white D. ludoviciana. 
I cannot determine satisfactorily what this genus should be called. It is not Ilerodias, 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 Demiegretta of Blyth, with his Ardea jugularis 1 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. 
1 Ardea jugularis, Blyth, Notes on the Fauna of Nicobar Islands, Jour. As. Soc. XV, 1846, 376. — Htrodias concolor, Bon. 
Conspectus, II, 1855, 121. 
