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The gas chromatographicmass spectrometric technique recently developed by Ryhage has been applied to the analysis of paraffins extracted from pasture plants, specifically, whole plant and leaves of spotted bur clover (Medicago arabica). Normal alkanes from C(18) to C(35) have been found. The C(29), C(31), and C(33) normal saturated hydrocarbons predominate and n-C(31) is the major component. In the range from C(24) to C(34) the ratio of alkanes with an even number of carbon atoms to those with an odd number is approximately 8 for the whole plant and 5 for the leaves. The distribution of paraffins is similar to that reported for cattle manure and also resembles that of some soils and sediments.

Three types of bacteria were isolated from samples of two carbonaceous chondrites and identified as common contaminants that are widely distributed.

The hydrocarbon composition of two algae, a golden-brown (Bot-ryococcus braunii) and a blue-green (Anacystis montana), has been investigated by gas chromatography-mass spectrometry. Both show distributions of aliphatic hydrocarbons of odd carbon numbers in the medium and high ranges of molecular weight, with maxima at n-C(17) and n-C(29) for B. braunii and n-C(17) and n-C(29) for A. montana. With the exception of the n-heptadecane of A. montana all the hydrocarbons are monoenes, dienes, or trienes. Since certain continental sediments and oils show similar distributions of alkanes with respect to carbon number, these organisms may be the precursors of the hydrocarbons in these formations.

Arenes of 1, 2, 3, 4 and more rings have been synthesized in a flow system by passing methane through silica gel at 1000 degrees C. Yields of 4.8 to 7.2 percent have been obtained per single pass. As determined by combined gas chromatography-mass spectrometry, the major compound synthesized that are of less than S rings are benzene, naphthalene, acenaphthylene, phenanthrene, fluoranthene, and pyrene. Under certain conditions ( presence of ammonia and water), small amounts of aliphatic hydrocarbons are also synthesized. Even-carbon-numbered hydrocarbons (aromatic as well as aliphatic) predominate, to the extent that about 97 percent of the total weight of the analyzed arenes have even numbers of carbon atoms.

By means of flow microfluorometry, the protein and nucleic acid contents of individual bacterial cells may be measured at the rate of several thousand cells per second. Accumulation of such information over a few minutes yields the composition distribution of the microbial population. These distributions have been determined at different times during batch growth of Bactillus subtilis, and the results indicate that the variance of cell composition decreases as the population passes through the exponential into the stationary phase. The relative abundance of endospores and vegetative cells as well as the protein distributions of these subpopulations may be readily determined from flow microfluorometry data. Experimental access to such details of microbial population dynamics should foster improved understanding of cell growth, spore germination, and spore formation kinetics.

A possible prebiotic synthesis of thymine has been achieved via the methylation of uracil with formaldehyde and hydrazine.