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BIOCHEMISTRY: ANDERSON ET AL. 881 13 5-HydroxymethyldUMP could be a hydrolytic side product of the hypothetical intermediate having a methylene bridge between the 5 position of dUMP and the no. 5 atom of tetrahydrofolate.7 In all solvents examined by R. E. Cline, R. M. Fink, and K. Fink [J. Am. Chem. Soc., 81, 2521 (1959)], 5-hydroxymethyldeoxyuridine migrated to the same position as 5-hydroxymethyluracil or was slightly slower, and thymidine and thymine always migrated far ahead of both. We could not detect radioactivity on our chromatograms in the region between the starting line and the position of thymidine and thymine (RF, 0.64). 5-Hydroxymethyluracil showed an RF of 0.49. From the background level radioactivity on the chromatogram, 5-hydroxy-methyldUMP could not account for more than 5% of the synthesis. 5-HydroxymethyldUMP does not appear to be an intermediate in the E. coli dTMP synthetase reaction.The uridine nucleotides, uridine diphospho-acetylmuramyl I-ala-D-glu I.lys. D-ala D-ala (UDP-M~urNAc-pentapeptide) and uridine diphospho-acetylglucosamine (UDP-GlcNAc), are substrates for a reaction catalyzed by a particulate enzyme prepared from Staphylococcus aureus in which a linear glycopeptide com-882 BIOCHEMISTRY: ANDERSON ET AL. PROC. N. A. S.

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Rare‐earth (RE) abundances are reported for several basalts, diabases, and gabbros. Compared with the RE distribution in chondritic meteorites, continental basic rocks are characterized by an enrichment of the light lanthanides. Intrusive basic rocks have lower RE contents and less fractionated RE distributions than continental basalts. Chill zones of the Stillwater and Bushveld complexes have different distributions which are Eu enriched and light RE depleted. Oceanic island basalts have RE abundances similar to those of continental basalts. Abyssal subalkaline basalts dredged from the mid‐Atlantic ridge and Eastern Pacific rise have RE distributions which are nearly chondritic. There is a depletion in La, Ce, Pr, and a broad maximum from Sm to Tb. Similar patterns are found in fresh basalts, slightly altered basalts, and in greenstones. Abyssal basalts that are more alkalic are not depleted in La, Ce, and Pr. The relationship of the RE data to hypotheses for the origin of ridge basalts is considered.

The relative elemental abundances of the rare-earth elements (REE) in a composite of 40 North American shales and in the average for 38 individual sediment samples are found to be identical with each other and with the average determined for sediments of the Russian Platform, to within an experimental uncertainty of ñ10% (standard deviation). The average RE distributions for 9 carbonates, 7 sandstones, 5 graywackes, and 8 ocean sediments are identical with the North American shale distribution to within a standard deviation of _15%, and the average for 9 shales lacks only one element of being so. Only 14 of the 38 individual sediment distributions are identical with the North American shale composite to within ñ15%, but fewer than 3% of the distributions differ in any part by a factor of 2 and fewer than 15% of them differ by a factor of 1.5. The spread in absolute RE content for sediments of a given type ranges from a factor of less than 3 for the ocean sediments to more than 30 for the sandstones. The average absolute RE contents increase in the order limestone, sandstone, graywacke, ocean sediment., shale. The absolute RE contents of the shale composites vary from somewhat more than 75 ppm to 335 ppm. The average total RE content of sediments is probably between 150 and 300 ppm. Preliminary results for separated minerals indicate that the bulk of the REE in the St. Peter sandstone is in the quartz, and in the Byron formation limestone it is in the carbonate. Experiments on adsorption of the REE on calcite are described.