Salmonella, Ascaris ova and Endamoeba coli cysts were recovered from more than 50 per cent of irrigation water samples contaminated with either raw sewage or primary-treated, chlorinated effluents. Only one of 97 samples of vegetables irrigated with this water yielded Salmonella, but Ascaris ova were recovered twice from 34 of the vegetable samples. The public health implications of these results are discussed.

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The synthesis of a number of vitamin factors by intestinal bacteria, both in vitro and in vivo, has been well established. There is also definite evidence in ruminants and suggestive evidence in the rat and in man that a part, at least, of the daily requirement of these factors is furnished by this bacterial synthesis (Najjar and Barrett, 1945). Some of the intestinal bacteria, Escherichia coli particularly, are capable of multiplying and producing their own cell substance in a medium consisting of an inorganic nitrogen source, salts, and glucose or some other simple carbon material

Glycerol (30%) inhibited or delayed the adsorption of Shigella bacteriophage on its host organism, S. flexneri II; glycerol also inhibited or delayed the burst of phage, whether or not adsorption was carried out in the presence of glycerol. Studies of the mechanisms of these effects showed that viscosity and osmotic shock probably were not responsible for either phenomenon. The inhibition of adsorption, however, was proportional to the concentration of glycerol, and appeared to be a function of the hydroxyl groups on the glycerol molecule. The inhibition of burst seemed to be related to the osmotic pressure outside the bacterial cells.

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