mind there was no doubt that the young birds had been removed upon the approach of danger; one of the adults was marked in a peculiar manner, so that there was no mistake in the identity of the pair. Doubtless this was an exceptional case, and in the vast majority of instances young birds perish in common with the other creatures which are overwhelmed by the ants. On the day following our arrival at the little village we boarded a waiting launch sent from the Madeira to meet us--the _Jayme_, she was called--and started on the final stretch down the stream; within an hour we reached the boundary-line of Matto Grosso and entered the great state of Amazonas. The Gy-Paraná had assumed the proportions of a mighty river; it is doubtless one of the largest, if not the longest affluent of the Madeira, and frequently the distance between banks was not less than half a league. The water was yellow and there was little current; frequently we ran into drifts of floating trees, branches, and patches of grass that had been washed out of the flooded areas. There was no opening in the tall, tropical forest which stretched into the distance and disappeared in one long, unbroken vista of deepest green. Toward evening we reached the mouth of the Gy-Paraná and entered the vast, muddy expanse of the Madeira; we crossed to the other side and landed at a small port called Calama, the home of Senhor Asensi, owner of the rubber-camps we had passed on the last days of our journey down the river. Senhor Asensi very courteously placed his comfortable home at our disposal and suggested that we remain as his guests until we had in some measure recuperated from our rather trying experiences, and we were glad to accept his hospitality. Practically every member of the party had suffered from frequent and severe attacks of fever, although half a gram of quinine had been taken by each one daily, and some of the _camaradas_ were so ill that they had to be carried ashore; the latter were sent to Manaos on the first available steamer for medical treatment. I was particularly eager to spend some time at Calama, as the locality appeared to offer unusual opportunities for zoological work. After a few days of thorough rest the Brazilian members of the party started up-river to Santo Antonio, for a tour of the Madeira-Mamoré railroad, while I remained to investigate the fauna of the region.