[A very little practice, it seems to the translator, would serve to enable any person of ordinary intelligence to apply this method, or several others which might be suggested. Other substances which would answer the same purpose would be dilute solutions of picric or chromic acid, of not more than one to one-half per cent., or one part to two hundred of water. Vinegar or acetic acid of the shops may also be used; the last to be diluted in the proportions of about one part in ten of water. The acids cited will coagulate and cause the germ disk to turn white or yellow in a few hours. Chromic is better than picric acid, as it coagulates the yelk also, but turns the latter much darker than the embryo or embryonic disk.--Tr.]
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