At Bahía Blanca, in the southern part of present Buenos Aires Province, Darwin rode inland into Patagonia with gauchos: he saw them use bolas to bring down "ostriches" (rheas) and ate roast armadillo. With FitzRoy, he went for "a very pleasant cruize about the bay" on 22 September, and about from the ship, they stopped for a while at Punta Alta. In low cliffs near the point, Darwin found conglomerate rocks containing numerous shells and fossilised teeth and bones of gigantic extinct mammals, in strata near an earth layer with shells and armadillo fossils, suggesting to him quiet tidal deposits rather than a catastrophe. With assistance (possibly from the young sailor Syms Covington acting as his servant), Darwin collected numerous fossils over several days, amusing others with "the cargoes of apparent rubbish which he frequently brought on board".