140 VOYAGE UP THE TAPAJOS. Chap. 11. 
from their mouths. When a bee or fly passed through 
the air near the water, they all simultaneously darted 
towards it as if roused by an electric shock. Sometimes 
a larger fish approached, and then the host of Piranhas 
took the alarm and flashed out of sight. The popula- 
tion of the water varied from day to day. Once a small 
shoal of a handsome black-banded flsh, called by the 
Acara (Mesonauta insignis). 
natives Acara bandeira (Mesonauta insignis, of Giinther), 
came gliding through at a slow pace, forming a very 
pretty sight. At another time, little troops of needle 
fish, eel-like animals, with excessively long and slender 
toothed jaws, sailed through the field, scattering before 
them the hosts of smaller fry ; and in the rear of the 
needle-fishes a strangely-shaped kind called Sarapo 
came wriggling along, one by one, with a slow move- 
ment. We caught with hook and line, baited with 
pieces of banana, several Curimata (Anodus Ama- 
