15. DEMIEGRETTA. ] 41 



Adult female in hrei'ding-2)luma<je. Similar to the male, but the 

 ornamental plumes slightly less developed. Total length 21 inches, 

 ■wing 10"2. 



Youncf. Paler and more sootj^ broAvn than the adults, and 

 bleaching often to a light earthy brown. No ornamental plumes 

 on the head, back, and chest. 



Adult birds, either in winter plumage or perhaps in the second 

 year, are blacker than in the summer plumage. Some of these 

 black-pluraaged birds have ornamental feathers, which looks as if 

 they were fully adult, and therefore they may be birds of the 

 second year, as it is quite evident that the greyer-plumaged ones 

 are very old and perfect in livery. 



The white streak down the throat is often absent or reduced to 

 a few spots. It appears to be absent equally in quite young birds 

 and in old ones also, and it may be the result of inherent melanism 

 in the species. 



The white form is exactly similar in size to the grey form, and, 

 ■when adult, has the same ornamental plumes. In the Pacific 

 islands the two forms appear to interbreed, and produce •white 

 young ones mottled or streaked ■with slaty grey. I have been 

 unable to recognize any of the many forms into ■which the Reef- 

 Heron has been subdivided by naturalists. Some birds are larger, 

 as ■will be seen by the measurements of the tarsi given in detail 

 below, and these larger birds have a slightly longer wing and a 

 heavier bill, but no specific distinctions can be founded on these 

 variations, which are very slight. 



" The colour of the soft parts is excessively variable. In the 

 adult the bare portion of the tibia varies from dark grass-green to 

 greenish plumbeous ; the back and sides of the tarsus and the 

 greater part of the toes are generally pea-green, sometimes duller, 

 sometimes yellower ; the front of the tarsus and the first joint of 

 the mid toe black, but sometimes these parts are green, only 

 patched or mottled with black, and sometimes the black extends 

 along the ridges of all the toes ; the colour of the bill and bare skin 

 in front of the eye varies from sienna-brown to chocolate; sometimes 

 the bill is a sort of light mahogany colour, and the bare skin a sort 

 of greenish brown ; usually the bills are yellowish at the tips ; the 

 lower mandible is generally lighter, sometimes bro^unish horny, 

 sometimes yellowish horny ; and in the breeding-plumage the whole 

 lower mandible becomes apparently a very decided, though dull 

 yellow ; the irides vary from bright to deep yellow. I suspect, 

 though we have not been able to work it out, that these diflerences 

 in colour are due both to age and to season." {A. 0. Hume.) 



It is with great hesitation that I have added the name of 

 Demiegretta euloi^liotes to the long list of synon3-ms of D. sacra. 

 Mr. Rickett has presented an adult specimen of D. eulophotes to 

 the Museum, and another one has been lent to me by the Eev. 

 H. H. Slater. Both birds appear to me to be Reef-Herons, and 

 have fully developed ornamental plumes. The yellow bill would 

 seem, at first sight, to constitute a specific character, but several 

 other specimens of undoubted D. sacra in the Museum have 



