Abstract
The down of young waterfowl was colored by injecting dyes into incubating eggs. The most satisfactory dyes tested were Fast Green FCF and Ponceau SX (Warner-Jenkinson Mfg. Co., St. Louis, Mo.) dissolved in distilled water at the rate of 14.6 and 6.0 g. per 100 cc.,re-spectively. From .12 to .42 cc. per egg was injd. under sterile conditions from 2 to 11 days before hatching. 70% of the young hatched and could be recognized in the field 23-32 days.

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