To the Editor:
—It seems to me that Dr. Alles has missed the intent of our report. We are not contending that our pollen extract was protein-free in the absolute sense of the word. We found that a pollen extract after a year's time gives no reaction to tests that were previously positive. We felt that this indicated a very definite quantitative change in the protein content and justified the statement made—that the extract contained no protein "so far as may be determined by the ordinary qualitative tests."With this extract we obtained results as good as those obtained by use of extracts containing considerable quantities of protein. We felt justified in believing, therefore, that this was another indication that quantitative reduction— if not absolute elimination—of protein had no effect on the active substance in pollen extracts.