The two ships sailed to the Río Negro in Argentina, and on 8 August 1833, Darwin left on another journey inland with the gauchos. On 12 August, he met General Juan Manuel de Rosas who was then leading a punitive expedition in his military campaign against native "Indians" and obtained a passport from him. As they crossed the pampas, the gauchos and Indians told Darwin of a rare smaller species of rhea. After three days at Bahía Blanca, he grew tired of waiting for "Beagle," and on 21 August, revisited Punta Alta where he reviewed the geology of the site in light of his new knowledge, wondering if the bones were older than the seashells. He was very successful with searching for bones, and on 1 September, found a near-complete skeleton with its bones still in position.