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no larg or oonsistent differenoe between 1951 and the reoent average. The data do not seem worth inaludior in this p er, esvecially since there 1a no assurame that the recorders were equally competent or adbared to aW uaiform standard. A decade of dates of 329 seasonal events at two stations, 33 miles apart# wre awlyzed wd omae with pr'ior records, Spin events during the decade 1935.'19415 were two weskit earlier than the iiim events at the same station in 161-M5, The northern station is tree days later in spriw than the southern one, *ioh i twice the epectation ner 6n Law. Th ditfference between the two stations Is leset in early spri and eatest in mdi r. The year-to yar variability of evets, as with their 1wn aver es tends to be greatest in .ar).y spriw, amd decreases progressively throu^ May, So= plants show little variability in date of first blooml they seem to be governed more by 1Afth of daylight than by crrent weathero White clover, the least variable plmt, has a st dar doation of P.4 dys, which is only a third of tha Peailing in other plants during the m onth, Sm birds show little variability in arrival date, despite the fact that they winter in or beyond the tr4os whore dhwaes in length of day are oh les The least variable birds were rose-breasted grosbeak (3.1 days) and upland plover (3.2 days), both only a third of the deviation prevailing In other contemporary migrants. Bird mirgration respond3 to cees in temerture much more qickly than the bloom of plants. In 1945 the om m of an early wa, period persisted in plants thro two moaths of subsequent cold. This mmnt caused early bloom in white trillim dospite the fat that it was still rr ddring the warm period. Duration of bloom in a cool dry June as cmp.rdwith a hot wet June, was protracted 60 to 8)1 peroent in various groups of plante.