SUMMARY : Solutions containing pectic materials were digested by solutions from cultures of 25 bacteria and examined chromatographically for breakdown products. Galacturonic acid and oligo-uronides were found with soft-rot Eminia spp. , Xan- thomonas campestris, Pseudomonas marginalis, Bacillus polymyma and Klebsiella aerogenes (galacturonic acid only). In an accompanying paper (Smith, 1958) the results of screening a number of cultures of bacteria for production of pectic enzymes have been described. To obtain further information on the nature of the enzymes concerned the pro- ducts of digestion of pectic materials by some of the bacteria were examined by paper partition chromatography. METHODS Cultures were grown in SM1 medium (Smith, 1958) and sampled at various times. The supernatant fluid after centrifuging was added to substrates of pectin or pectic acid at pH 7.5 or 5.5 as for viscosity tests-in some cases the pro- portion of culture was increased from 74 to 10 %-and incubated for periods of up to 3 days. In most cases loss of viscosity was practically complete in the first 24 hr. but further diminution in the ethanolic precipitate occurred on longer incubation. Samples for chromatography were concentrated and purified because tailing of the crude digests made identification of spots on the chromatograms uncertain. The following simple procedure purified the solutions by removing higher uronides and some unidentified material which practically coincided with galacturonic acid on the chromatograms. Absolute ethanol (5 ml.) was mixed with 5 ml. of digest and the precipitated colloidal material centrifuged off. The calcium salts of the low oligo-uronides were then precipitated by adding a drop of 1 yo CaC1, solution and 10 ml. of absolute ethanol. The precipitate was centrifuged down, drained and suspended in 1 ml. of distilled water. Solution was completed by adding a pinch of Amberlite I.R. 120 cation ex- change resin in the hydrogen form; 0.1 ml. of this solution was spotted on the chromatogram. Marker spots on the chromatograms were (a) 5pl. of a 0.5 yo (w/v) solution of galacturonic acid; (b) 50 pl. of a solution containing galacturonic acid and di-galacturonic acid, obtained by digestion of pectic acid with fungal pectin glucosidase (PG) and purified by ethanol precipitation.