Note 57 — Chapter V · FROM PARÁ TO MANAOS.

I soon became convinced after leaving Pará that the faunæ of our different stations were not repetitions of each other. On the contrary, at Breves, Tajapurú, Gurupá,—in short, at each stopping-place, as has been seen,—we found another set of inhabitants in the river, if not wholly different from the last, at least presenting so many new species that the combination was no longer the same. It became at once very important to ascertain whether these differences were permanent and stationary, or were, in part at least, an effect of migration. I therefore determined to distribute our forces in such a way as to keep collecting parties at distant points, and to repeat collections from the same localities at different seasons. I pursued this method of investigation during our whole stay in the Amazons, dividing the party for the first time at Santarem, where Messrs. Dexter, James, and Talisman separated from us to ascend the Tapajoz, while Mr. Bourget remained at Santarem, and I, with the rest of my companions, kept on to Obydos and Villa Bella.—L. A.