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 Nov., 1910 NESTING NOTES ON AMERICAN EARED AND PIED-BILI, ED GREBES 18') gling platforms of large, rank, green dock stems, cat-tail stalks, rushes, weeds and grass, usually floating in comparatively open water, or in very sparse growths of cat-tails, with no apparent attempt at concealment. The nests were very flat, the nest cavity often being actually below water level, and the eggs in most cases be- ing wet. How these eggs with damp shells retained enuf heat either from the parent or from the sun's rays to hatch them, is a problem which I have been un- able to solve. And as a matter of fact quite a perceptible percent of old nests ex- amined contained addled eggs. This was equally true of both species. The Pied-bills' nests, on the other hand, were compactly-bilt structures of uni- form size and shape, composed entirely of decaying vegetation of a uniform dead brown color, well bilt up above the surface of the water and fairly well cupt. They were nearly always bilt in a rather dense growth of cat-tails which afforded them reasonable concealment, altho a few exceptions were noted where nests had been bilt in exposed positions at the edge of open water with no concealment whatever. Both species seemed to choose sites where the water was from two to three feet Fig. 60. NEST OF AMERICAN EARED GREBE SHOWING CARELESS MANNER m WINCH EGGS ARE cOVeRED BY 'ARENT BIRDS deep, but this was probably due to the fact that suitable cover grew in this depth of water. As has been said, the nests of the two birds were radically different in ap- pearance, and this was further exemplified in the manner in which the eggs were covered during the absence of the parents. The Eared Grebes usually covered the eggs very carelessly with a thin layer of grass or rushes, and in many cases the eggs could easily be seen thru the covering. The Pied-bills, on the contrary, cov- ered their eggs very carefully with a thick layer.of moist decaying vegetation of the same appearance as the nest proper, spreading it evenly over the top of the nest to a depth of two inches or more; and the nest so covered presented a remark- able example of protective concealment, looking exactly like the water-soakt tops of dilapidated musk-rat houses. In fact, I smile to think of the number of these uninteresting looking mounds of filth, which I must have past unheedingly before I discovered the secret of their hidden tresures.