At Santa Cruz we saw several of these birds.

They were excessively wary: I think they could see a person approaching when too far off to be distinguished themselves.

In ascending the river few were seen; but in our quiet and rapid descent many, in pairs and by fours or fives, were observed.

It was remarked that this bird did not expand its wings, when first starting at full speed, after the manner of the northern kind.

In conclusion I may observe that the Struthio rhea inhabits the country of La Plata as far as a little south of the Rio Negro in latitude 41 degrees, and that the Struthio Darwinii takes its place in Southern Patagonia; the part about the Rio Negro being neutral territory.