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J. Delacour—Rheas



[Rhea americana ) and Darwin’s Rhea [Rhea pennata). Some ornotho-

logists have considered the latter as belonging to a special genus

(.Pterocnemia) which, to my mind, has no sound foundation, as differences

between the two birds, if well marked, are neither great nor important

enough. In both species, cocks and hens are alike in plumage and

shape, the males usually looking larger and coarser. The only safe

way to tell the sexes apart is to watch their attitudes in the breeding

season, when it is easy to differentiate between them while they are

calling and displaying.


Common Rheas are found from the north of Brazil to the Rio Negro

River in the Argentine. Three distinct geographical races or sub¬

species occur : R. a. americana in the north of the range, a dark and

brownish bird, seldom imported and not quite hardy in Western Europe ;

R. a. intermedia, from S. Brazil and Uruguay, rather smaller, ashy-

grey with a whitish buff neck and a grey interscapular patch, also

very seldom brought over ; the third form, from the Argentine (R. a.

albescens) is the Rhea commonly seen and well acclimatized in Europe.

Of a large size, it is ashy-grey, with most of the neck and a large patch

on the chest black.


The White Rhea is only a selected albinistic variety of the above

Argentine race. It is a very fine bird, snow white, with black markings

on the neck and chest, often rather less apparent than in the grey form,,

yellow legs and bill, and pale blue eyes. It is just as strong and hardy

as the Grey Rhea, and much more ornamental. In a field, at some

distance, it shows up very much better against a green background.


Grey Rhea chicks in down are browmish buff marked with dark

brown stripes ; they very soon grow feathers and then look exactly like

miniature adults. White Rhea chicks are white, often with a few

brown patches, which soon disappear. If Grey and White Rheas are

crossed the result is as a rule grey or white birds ; only twice or three

times have I seen intermediate birds, buff or cream-coloured, looking

rather ugly and untidy. Parti-coloured birds do not seem to exist.


Darwen’s Rheas (R. pennata) live south and west of the Common

Rhea, from the highlands of S. Peru and Bolivia, N.W. and S. Argentina

to Patagonia. Three races occur, according to Chubb : R. p. garleppi

in the north of the range, R. p. tarapacensis in N. Chili, and R. p ,



