1 3 8 
Barrows oh Birds of the Lower Uruguay. 
[July 
50. Taenioptera coronata ( Vieilli). — The preceding de- 
scription is applicable to this bird except that I did not note its 
presence at Concepcion after September 1 until the following 
April. This species frequently persecutes smaller birds in a 
way which seems to imply pure love of mischief. One afternoon 
in July, when the river had fallen some feet after an unusual 
rise, I was walking along the lines of drift left by the falling- 
water, and watching the different birds which were picking up 
insects or other food from the windrows. A score or two of the 
little chestnut-backed Centrites were running about, and here 
and there a Tcenioptera was looking quietly on. Suddenly I 
heard a chirp of distress, and looking up saw one of these small 
birds apparently making every effort to escape from a Tcenioptera , 
which was following in full chase. The two birds were hardly a 
length apart and both going at full speed, doubling and dodging 
in a way that would have done credit to a bat. The chase 
lasted perhaps half a minute when the smaller bird alighted and at 
once the other also alighted and began running about unconcern- 
edly and picking up food. But the instant the smaller one 
made a start, his enemy was at his heels (or more properly his 
tail) again, and he was forced to alight. This was repeated so 
often that I was on the point of shooting the pursuer, when 
without any notice he flew quietly off and resumed his usual 
demeanor. Afterwards I saw the same proceeding quite fre- 
quently — the tyrant being in every case T. coronata (except 
once when I think it was nengetd) , but the victim was person- 
ated at different times by certainly four or five different species ; 
all small, but all very strong on the wing. So far as I could 
judge, the pursuer never actually touched the pursued ; nor did 
he ever appear to stop, or pick up anything which the other 
might have dropped. It looked like a case of simple spite, for 
even if there were twenty other birds about, one seemed to be 
selected and followed without regard to the rest. Moreover, 
neither species was nesting, for this occurred in mid-winter, and 
while the Centrites was in flocks, and if it were only from pug- 
nacity there would seem to be no reason why other birds should 
not share in the attention. 
My only explanation is that it was an amusemeiit. in which the 
larger bird indulges simply for the pleasure derived from the 
exercise of his power. 
