Carbylamine, produced in ethyl alcohol solution from various amino compounds under identical condition, has been estimated by hydrolysing it to formic acid. The amount formed does not exceed 35% of the theoretical value and decreases considerably on dilution of the reaction mixture. Substitu­tion of + I groups in aniline increases the yield whereas —I groups diminish it. In the mixtnre of iodoform and aniline, the reaction is induced photochemically in the absence of alkali. Urea has also been found to afford an isonitrile.