Fulica americana 129 630. Lake Tamescal, 420 ft., Alameda Co., Calif. Once I counted 22 coots on this lake today. Found four structures, 3 of them old nests of which 2 are still functional, and 1 may still be defended. The fourth structure is some sort of a platform that seems to be under construction now. There is a lot of dead material in it but there is also quite a bit of green stuff. The general looseness of the leaves, plus the lack of any fecrements further indicates the newness of the structure. About 3 p.m., the 3 pairs were seen in counting play, leading finally to the & mounting the ♀ but not copulating. The ♀ was sitting on the shore. Afterward both birds preened for a short time, the ♂ going onto the water to do it, the ♀ staying on shore. Shortly she was back teasing (?) him, making a barely audible sound, pecking at him, and generally disturbing him. - Later the "laughing" of the ♀ and the "crow" of the ♂ seem to be comparable calls. Several times this afternoon I saw two birds in display positions (to not displaying) giving these two different calls simultaneously - at least since the proper birds proved to be ♀ + ♂ by the usual call. The birds of this year are proving difficult to distinguish now. Only about two of them have unmistakably gray mottled bills, but several of the ones with ivory bills have noticeably paler pied-masking which by their general behavior, I gather are immature birds. About 5 p.m. 2 Cooper Hawks flashed over the lake, the only response from the coots was complete