208 BIRDS OF LA PLATA 
but I have never taken more than three eggs from 
one nest. I mention this because I have seen it stated 
that four or five eggs are sometimes found. 
I trust that no reader of this sketch imagines that 
I robbed all the eggs contained in so many nests. I 
did nothing so barbarous, although it is perhaps 
“ prattling out of fashion’ to say so; but with the 
destructive, useless egg-collecting passion I have 
no sympathy. By bending the pliant rushes down- 
wards the eggs can be made to roll out into the hand ; 
and all those which I thus took out to count were 
put back in their wonderful cradles, I had a special 
object in examining so many nests. A gaucho boy 
once brought me a nest which had a small circular 
stopper, made of the same texture as the body of the 
nest, attached to the aperture at the side and when 
swung round into it fitting it as perfectly as the lid 
of the trap-door spider fits the burrow. I have no 
doubt that it was used to close the nest when the 
bird was away, perhaps to prevent the intrusion of 
reed-frogs or of other small birds ; but I have never 
found another nest like it, nor have I heard of one 
being found by any one else; and that one nest, 
with its perfectly-fitting stopper, has been a puzzle 
to my mind ever since I saw it. 
