Cincinnati, Jan. 15, 1903.
To the Editor:
—In a recent number of The Journal (Jan. 10, 1903, p. 91) Dr. Alfred C. Croftan has published a series of tests said to be characteristic of adrenal tissue or extract, by means of which he proposes to differentiate adrenal tissue and hypernephromata.One of the most striking and constant of these tests is described as "The Power to Decolorize Iodin-Starch Solution." The test is made in the following manner:Equal portions of starch solution having been distributed in several test tubes, hypernephroma extract was added to one-half of them, and then one drop of an alcoholic iodin solution was added to each. Those tubes that contained no hypernephroma extract immediately turned blue and remained blue, whereas those tubes that contained hypernephroma extract turned blue for an instant only and became immediately decolorized.It seemed to the writer to be important that this