672 
U. S. P. R. R. EXP. AND SURVEYS — ZOOLOGY GENERAL REPORT. 
lanceolate, and reaching nearly ita length beyond the tip of the tail, each feather well defined 
and the wehs not decomposed. 
The body generally in the adult is slaty blue ; the head and neck glossed with bluish purple ; 
the concealed portions of the feathers purplish brownish red. There is no trace of white on the 
throat. The bill in life is said to be ultramarine blue at the base, shaded into black towards 
the point ; the bare space between it and the eye, as well as the edges of the eyelids, ultra- 
marine. The iris pale yellow ; the legs, tarsi, and toes, black. 
The young bird is pure white ; the head smooth, and the feathers without the decomposed 
webs. The scapulars are not elongated. The iris is white ; the bill light blue, blackish at the 
end ; the skin around the eyes and the base of the bill light yellow ; the legs light green. 
Birds changing show a confused patching of white and blue. 
The young bird in white dress is much like the Garzetta candidissima, but is without any of 
the plumes or crests of the latter species, and almost always shows here and there a trace of 
blue, instead of being pure white. The middle toe is much longer. The feet are entirely 
greenish to the claws (livid black in the dry skin) instead of having the toes yellowish, and the 
base of the bill is without the abruptly defined yellow portion. 
According to Lichtenstein, "the A. caeridea of Linnaeus has the feathers of neck and occiput 
and ' the scapulars well defined and linear ; the bill black; the legs brown, with yellow toes. 
Length, 18 inches ; bill, 2.50 ; tarsus, 3. Hab. — Cayenne. The North American A. caerulescens 
has the same feathers with the fibres loose ; the bill whitish at base ; the legs and toes greenish. 
Length, 22 inches ; bill, 3 ; tarsi, 4." The species he refers to first is evidently a true Herodias. 
List of specimens. 
Catal. 
No. 
Sex. 
Locality. 
When 
collected. 
Whence obtained. 
Collected 
by- 
Length. 
Stretch 
of wings. 
Wing. 
Remarks. 
3040 
8 
Liberty county, Ga. . .. 
Spring, 1846.. 
22.00 
30.00 
12.00 
4554 
B68U 
S 
29.50 
39.50 
11.00 
Eyes dark blue ; iris whitish ; legs 
and feet light green. 
9300 
Prairie Mer. Rouge, La. 
9493 
Lower Rio Grande, Tex. 
ARDETTA, Gray. 
Arietta, Gray, List of Genera, Appendix, 1842, 13. Type Ardea minuta, L. 
Jlrdeola, Bonaparte, Syn. 1828. Type Ardea exilis, L. Not Jlrdeola, Boie, Isis, 1822. 
Ch. — Bill slender, acute; both mandibles about equally curved. Legs very short; tarsi less than middle toe. Inner toe 
much longest. Claws long, acute. Tarsi broadly scutellate anteriorly. 
Tail of ten feathers. Neck short. Body much compressed. Head smooth ; the occipital feathers somewhat lengthened ; the 
lower neck bare of feathers behind. No plumes. Plumage compact, lustrous ; uniform above. Sexes differently colored. 
This genus embraces the smallest known species of heron, and has representatives in all 
quarters of the globe. 
