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Jan.,1910 FOSSIL BIRDS FROM QUATERNARY OF SOUTHERN CALIFORNIA 15 less birds. The characters of the sternum and the humerus suggest those of the sailing fliers. Those California bird students who have seen the Condor towering above the Turkey Buzzards groupt about a carcass probably have a good mental picture of the way this great bird must have appeared among the Condors gathered about the vulture feast at the asphalt beds during Quaternary time. ABNORMAL BIRDS' EGGS By A.M. INGERSOLL W?TH FOUR PHOTOS BY THE AUTHOR O OLOGICAL abnormalities are occasionally found by all collectors; but few, probably, have had the experience of examining a set of eggs showing such gradual variation in size,*.as is illustrated in figure 7, accompanying this article. The seven eggs measure in inches, 1.06>(.81, 1.04>(.76, .96>(.76, .93>(.73, .84>(.69, .82>(.68, .81X.65. Each egg appeared to contain the usual proportionate amount of yolk. This Red-shafted Flicker, being inexperienced in nest building or too lazy to excavate a proper home, took possession of allargo decayed-out hollow in an immense cottonwood tree. The entrance to this natural cavity was large .?Fig. 7. SET OF SEVEN EGGS OF THE RED-SHAFTED FLICKER, COLLECTED AT RAMONA, ? CALIFORNIA, APRIL 25, 1888 enough to admit my head. This set of freaks were followed by eggs of normal size in the same nest. Runts are commonly infertile. The yolk is generally present but sometimes much reduced in quantity and occasionally entirely lacking. Barring out species laying but a single egg to a set, I can only recall three instances in which a runt was positively the first egg deposited. It seems .reasonable to believe such runts as are laid at the commencement of a set to be eggs of young birds, and those that are laid at completion of a set to be the final product of old birds on the verge of barrenness or enfeebled by excessive laying. I have never known of a set with runts, or such deformities as lopsided eggs, granulated shell texture, wrinkled or warty shell, to be followed by others containing similar abnormalities. This would seem to indicate that such malformations are not caused by a perma- nent individual peculiarity of the parent bird, as apparently is the case when cer- tain individuals habitually lay eggs departing from normal in coloration, size or