38 
ALTRICIAL GRALLATORES — HERODIONES. 
different species, will feed quietly near one another ; but let another approach, and 
before it is within a hundred yards it will be at once pursued, and the attempt made 
to drive it away ; and the pursuer and pursued will always be of the same species. 
But if the approaching bird is of a species different from any of those feeding, it may 
descend among them without being disturbed. In this petulance to one of its own 
species a Heron never makes any mistake. Even the small Blue Heron, whose young 
are for a year as white as the White Egret, never mistakes the latter for one of its 
own kind. It is this habit of attacking only birds of its own species that first led 
Mr. Moore to regard the rufa and the Pealei as identical ; for the purple chase the 
white, and the white pursue the purple, but they never tease any other species. 
These birds use their legs and toes to scrape the oozy bottom, or among the 
plants, in order to uncover their hidden prey. It is a mode peculiar to this species, 
and not to be mistaken for that of any other ; but both of the two varieties per- 
form this act in the same manner, and their unity of action in other respects is said 
to be very conspicuous. No other Heron is so awkward, impetuous, and clumsy a 
fisher. In clear water it gives chase to its prey with expanded wings, which are flirted 
up and down, or are held open, as it runs or hops, sometimes out of the water, some- 
times turning entirely round. In all these wild and awkward movements the two 
forms exactly imitate each other. In size, too, they are exactly the same. As chasers 
the two forms are not only alike,- but are superior to all others of the family. They 
pursue their prey — which is almost exclusively fishes — by hasty steps, hops, and 
doublings. Instead of being shy and suspicious, as Audubon states, they are, ac- 
cording to Mr. Moore, almost as unsuspicious as the Green Heron. This bird breeds 
in company both with its own and with other species, such as egretta, candidissima, 
ludoviciana, virescens, etc. If, when wounded, it falls into the water, it can swim 
readily. So far as Mr. Moore’s experience goes, the proportion in numbers of the 
white to the blue is as one to eight. 
Two eggs of this species, obtained by Mr. Audubon in 1832 on the Florida Keys, 
are of a rounded oval shape, are larger than the eggs of the Pealei, and the shell 
is thicker and rougher. They have the uniform greenish-blue shading common to 
the eggs of all our true Herons, — ■ a washing of Prussian blue with a slight tinge of 
green. One (No. 98) measures 2.11 inches in length, by 1.65 inches in breadth. The 
other (784) measures 2.20 inches by 1.66. 
Genus HYDRANASSA, Baird. 
< “ Dcmicgretta” (nec Blytii), Baird, B. N. Am. 1858, 660 (part). 
= Hijdmnassa, Baird, B. N. Am. 1858, 660, in text. Type, Ardca ludoviciana, Wils.,=A. tricolor, 
Muller. 
< Erodius, Reichenow, J. f. 0. 1877, 268 (includes Dichromanassa, Lcpterodius, Herodius, and 
Garsetta). 
Gen. Char. Small Herons of variegated colors, white beneath, plumbeous above, the hill 
equal to or longer than the tarsus, and very slender. Bill long and slender, but little compressed ; 
the upper and lower outlines appreciably concave about the middle, the gonys almost straight and 
but slightly ascending, the culrnen gently convex towards the end. Mental apex reaching less 
than one third the distance from the middle of the eye to the point of the bill, but, at the same 
time, about as far forward as the anterior end of the nostril ; malar apex reaching about as far for- 
ward as the frontal feathers. Tarsus long, about equal to the bill ; middle toe about two thirds 
the length of the tarsus, the hallux about half as long as the latter ; bare portion of the tibia 
decidedly shorter than the middle toe. Adult, with feathers of the neck, except throat, distinctly 
