I^S Barrows o?i Birds of the Lo-vcr Uruguay. [July 



50. Tsenioptera coronata {VleilL). — The preceding de- 

 scription is applicable to this bird except that I did not note its 

 presence at Concepcion after September i 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 T^nioptera 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 TcEiiioptera, 

 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 neng-eta)^ but the victim was person- 

 ated at different times by certainl}' 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 vip 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 Centi'ites 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 ainusement in which the 

 larger bird indulges simply for the pleasure derived from the 

 exercise of his power. 



