What is one of the quinoline bases, obtained from coal tar as an oily liquid, C11H11N; also, any one of several substances metameric with, and resembling, cryptidine proper called?

cryptidine — One of the quinoline bases, obtained from coal tar as an oily liquid, C11H11N; also, any one of several substances metameric with, and resembling, cryptidine proper. (Webster's 1913.)

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