12. Progne tapers. (Linn.),

—This species appeared in the spring at about the same time as the preceding—about the middle of September— and for some time I did not distinguish it from the female of that species.

In general habits the two species are quite similar, but the notes are somewhat different and the present species is more often found away from the houses than is the common Martin, nor does it, so far as I know, ever breed under the eaves of dwellings. Probably the greater number breed in natural hollows of trees, or in the abandoned nests of other birds. I once noticed several hovering about Woodpeckers’ holes in a tall dead tree, and early in November, 1880, saw a female carry a feather into a deserted nest of the Oven Bird (Furnarius rufus), Where I caught herin my hand as she was arranging the materials of a nearly finished nest.