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 Sept, 1915 ESTIMATED AVERAGE AGE OB THE HERRING GULL 183 If the plumages have not been correctly diagnosed the results will be thrown into error. This .might be, if some first-year birds wore second-year 'plumage, which is unlikely, as if so there would be more intermediates between typical first, and second-year plumages in the fall than one actually does find. That some older birds wear second-year plumage, or second-year birds adult plumages seems more probable, but here the error should fall on one side as frequently as on the other and make no difference in the final results. It is possible that the counts are not sufficiently great to give the true pro- portions. Larger counts would of course be more reliable; but in the writer's opinion those made are sufficiently large for approximate accuracy. If the habits of young and old vary so that any age favors the region where the observations were made more than the others, this would result in an erron- eous proportion being obtained. Familiarity with the Herring Gull in various parts of its winter range leads the writer to believe that young or old do some- what favor certain regions, but that the point where the observations were made is not such a region and that the counts are representative. SUMMARY In view of the difficulties of successfully estimating the age which a species of bird reaches in nature, an estimate based on the proportion of young to old is of interest. To repeat, such an estimate from two season's observation of the Herring Gull gives average age attained by first-winter birds 6.0 years, second- winter birds 16.2 years, which implies a very heavy mortality between the first and second winters. Very likely the mortality continues heavy for another year or more and the normal age of the species is distinctly greater than the average age reached by seeon. d-winter birds, perhaps between 15 and 20 years, but this is mere guess-work. The writer considers the method here used one of the best, when available for determining age; but results obtained with it by one observer in one locality in so short a time can not be greatly relied upon. New York City, June 11, 1915. A LATE NESTING RECORD FOR THE CALIFORNIA WOODPECKER* By HARRIET WILLIAMS MYERS OR TWO seasons, at least, the same hole in a telephone pole that is daily passed by hundreds of street cars and automobiles, has been the home of a pair of California Woodpeckers (Melanerpes formicivorus bairdi). There are plenty of oak and other trees nearby, but the birds seem to have a' fondness for this pole which is near a group of poles on the corner of Pasadena Avenue and Avenue 62, Los Angeles, only a short distance from the Arroyo Seco. The hole is about thirty feet from the ground and is badly worked and split down. From a small round opening it has become an almost square one nearly twice as large as needed. While nesting birds have been recorded for every month in the year in Cali- fornia, I had thought July to be the latest for these woodpeckers, and was, there- fore, rather surprised to find that this nest-pole contained squealing young on September 11. It was after six o'clock that I passed near the corner on this day
 * Read at the A. O. U. Congress, San Francisco, May 18, 1915.