148 



NOTES ON BRAZIL. 



Seals were abundant in the month of the river in the years 1808 and 

 1809, five years afterward their numbers were greatly diminished ; a 

 fact which may,^ perhaps, be allowed to furnish additional evidence of 

 the propensity of some sorts of fishes to change their abode, when 

 much disturbed by the frequent appearance of vessels. Small sharks, of 

 the shovel-nose kind, continue to be very numerous. 



A fish, here called the Bagre, and very common on every part of 

 the coast, we thought the most palatable when taken off a sandy bottom. 

 It is about twelve inches long, formed much like the Dog-fish, has a 

 large head, the bones of which are uncommonly hard ; two fins on the 

 side and one on the back, all of them long in proportion to the size of 

 the fish. The anterior ray of the fins is a strong serrated bone, sharply 

 pointed, which it has the power of erecting, and fixing at right angles 

 with the line of the body, so firmly, that, with the utmost force of 

 both hands, I have been unable to change its position. This firmness 

 depends, not on the strength of the muscles employed in its erection, 

 but on the form and hardness of the joint, which is a sort of compound 

 hook, working upon an upright pin, altogether unlike what I have 

 noticed in any other fish. Nature appears to have intended this for 

 a defence, and a more secure one it is difficult to conceive. The Bagre, 

 when caught, utters a loud grunting noise, with other apparent signs 

 of anger. It lives long out of the water, and is with difficulty killed 

 by blows. 1 observed in the plate of the skull, between the eyes, a 

 small aperture, covered with a thin whitish membrane, and imagined 

 that, through this, it might be killed by touching the brain. We 

 accordingly introduced a filament, taken from one of the bass cables, 

 which produced an immediate paralysis, and the fish died without 

 farther suffering. This aperture may, probably, be a distinguishing mark 

 of the species, which, I believe, has not hitherto been described. 



There is a fish, called by Wilcocke, in his History of Buenos 

 Ayres, the Armado. I do not recollect seeing more than one specimen 

 answering to his description, which we caught, I think, off^ Ensinado. 

 It appeared to me to be of the same species with the Bagre ; and 



