72a Study Area #2 April 11 Pair of chiofensis foraging in leaves at the base of an amate. Watched them work over the base of the tree and in the large leaves on the ground. They flip leaves one at a time to get at insects - often they through them for 1/2 foot or so. This pair foraged at the base of the tree for 15 minutes then flew into the vines in the understory where they foraged a short time before flying across the stream to a guanacaste tree. About 40 yds down stream we found the nest of a pair of nigricaudalis - humilis rulemedits, in an acacia between two omates (See map.) Later in the day we saw two pairs of nigricaudalis - like birds and a pair of chiofensis together in a patch of vines just across the river from the nest. Collected one pair of the small wrens and Bonifacio collected three other birds just downstream and across the stream from the car. I found a pair of chiofensis in a stand of guanacaste, amates, and vines across the river from the nest of the small wrens too with the nest. Hence at least two pairs each of the two species were present in our study area. We did not locate the range of the second pair of small wrens. There was no sign of habitat differences between the large or small wrens in our study area. The map gives the impression that the groups replaced one another spatially but this is an over simplification.