250 
BTKDS OF BRITISH BURMAH. 
Genus DEMIEGRETTA, Bl 
615. DEMIEGRETTA SACRA. 
THE BLUE REEF-HERON. 
Ardea sacra, Gm. Syst. Nat. i. p. 640 ; Hume, Nests and Eggs, p. 618. Ardea 
jugularis, Forst., Wagl. Syst. Av., Ardea, sp. 18. Demiegretta concolor, Bl. 
J. A. S. B. XV. p. 372. Demiegretta sacra, Salvad. Ucc. Born. p. 346 ; Wald. 
Ibis, 1873, p. 318 ; Hume, 8. F. i. p. 254, ii. p. 304 ; Hume ^ Bav. S. F. vi. 
p. 481 ; Hume, S. F. viii. p. 114. Herodias concolor, Bl. B. Burm. p. 160. 
Description. — The adult in full breeding -plumage is everywhere of a deep 
blackish slate-colour ; the feathers of the head almost black ; the feathers 
of the upper breast greatly elongated^ as are those of the middle back, 
some of the latter disintegrated ; the elongated feathers of a paler slaty 
grey, those of the breast not exceeding 3*5 inches in lengthy those of the 
back reaching quite to the end of tlie middle tail-feathers. In most 
specimens there is a somewhat brownish ashy tinge on the abdomen and 
vent-feathers. In some adults there are not more than one or two white 
feathers on the whole chin and throat ; in others there is a well-marked 
pure white streak from the tip of the chin down the centre of the throat 
fully four inches in length, and between these two extremes every inter- 
mediate amount of white occurs. There is a broad full occipital crest 
about an inch long. {Hume.) 
A certain proportion of these Herons are pure white throughout_, with 
dorsal and pectoral plumes developed as in the ashy birds above described^ 
except that the dorsal plumes are sometimes longer, exceeding the tail by 
one inch. It seems to be generally recognized now that the white birds 
and the ashy ones belong to the same species ; in fact the nestling birds 
are sometimes white^ sometimes ashy and occasionally pied ashy and white, 
but the old birds apparently never exhibit this latter pied plumage. 
Length 21 to 24 inches, tail 3 to 4*25, wing 9*85 to 11-75, tarsus 2*7 to 
3-1, bill at front 2-65 to 3*5. {Hume.) 
In nnnhreeding -plumage the pectoral tuft and the dorsal train are 
wanting. 
An allied species D. gularis differs in having the whole chin, throat and 
sides of the head as high up as the gape and the ear-coverts white, and it 
is also larger than D. sacra. 
The Blue Reef-Heron occurs along the whole coast of British Burmah. 
It is found in the Andaman and Nicobar Islands, and it is spread along 
the shores of the whole of Eastern Asia, from Japan southwards to the 
islands of the Archipelago, Australia, and some of the islands of the 
Pacific Ocean. 
