Comparatively little work has been published upon the bacteriological investigation of the urine in the healthy woman either normally or during pregnancy and the puerperium, and the findings in such work as has been published are contradictory. In 1912, Leith Murray, Stenhouse Williams and A. J. Wallace, working together upon the coliform organisms in the female urinary tract, came to the conclusion that typical Bacillus coli is found in a considerable percentage of all female urines taken under conditions precluding all sources of contamination, and that ordinarily they have no apparent pathological significance. John Hewitt, in 1923, published a report upon 34 cases of urinary infection during pregnancy and the puerperium. He agreed with Leith Murray and other workers who had quoted figures to show that healthy pregnant women may have B. coli in the urine in the absence of pus cells.